Category: Hem/Onc Updates

ENHERTU® after Endocrine Therapy in Advanced Breast Cancer

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SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. It is estimated that in the US, approximately 310,720 new cases of female breast cancer will be diagnosed in 2024, and about 42,250 individuals will die of the disease, largely due to metastatic recurrence.

The HER or erbB family of receptors consist of HER1, HER2, HER3 and HER4. Approximately 15-20% of invasive breast cancers overexpress HER2/neu oncogene, which is a negative predictor of outcomes without systemic therapy. Patients with high levels of HER2 expression (IHC 3+ or 2+/FISH+) are classified as HER2-positive. Patients with HER2-positive metastatic breast cancer are often treated with anti-HER2 targeted therapy along with chemotherapy, irrespective of hormone receptor status, and this has resulted in significantly improved treatment outcomes. Tumors that are not classified as HER2-positive are classified as HER2-negative. Despite being classified as HER2-negative, majority these tumors still have some level of HER2 expression.

About 70% of breast tumors express Estrogen Receptors and/or Progesterone Receptors, and Hormone Receptor (HR)-positive/HER2-negative breast cancer is the most frequently diagnosed molecular subtype. It is estimated that approximately 60-65% of HR-positive/HER2-negative breast cancers are HER2-low and potentially an additional 25% may be HER2-ultralow. These patients are often treated with single agent endocrine therapy, endocrine therapy in combination with CDK4/6 inhibitor, or chemotherapy. Resistance to hormonal therapy occurs in a majority of the patients and there is therefore an unmet need for agents with novel mechanisms of action. Further, there are no targeted therapies specifically approved for patients with HER2-low or HER2-ultralow expression, prior to chemotherapy.

ENHERTU® (Trastuzumab Deruxtecan) is an Antibody-Drug Conjugate (ADC) composed of a humanized monoclonal antibody specifically targeting HER2, with the amino acid sequence similar to Trastuzumab, a cleavable tetrapeptide-based linker, and a potent cytotoxic Topoisomerase I inhibitor as the cytotoxic drug (payload). ENHERTU® has a favorable pharmacokinetic profile and the tetrapeptide-based linker is stable in the plasma and is selectively cleaved by cathepsins that are up-regulated in tumor cells. Unlike KADCYLA® (ado-Trastuzumab emtansine), another ADC targeting HER2, ENHERTU® has a higher drug-to-antibody ratio (8 versus 4), released payload easily crosses the cell membrane with resulting potent cytotoxic effect on neighboring tumor cells regardless of target expression, and the released cytotoxic agent (payload) has a short half-life, thus minimizing systemic exposure.

DESTINY-Breast06 is a global, randomized, open-label Phase III trial evaluating the efficacy and safety of ENHERTU® versus chemotherapy in patients with HR-positive, HER2-low, or HER2-ultralow advanced or metastatic breast cancer. This study enrolled 866 patients (N=713 for HER2-low and N=153 for HER2-ultralow). HER2-low was defined as IHC 1+ or 2+ or FISH negative and HER2-ultralow was defined as IHC 0 with membrane staining. Patients were randomized 1:1 to receive ENHERTU® 5.4 mg/kg every 3 weeks (N=436) or physicians choice of chemotherapy which included Capecitabine, Paclitaxel, or nab-Paclitaxel (N=430). Patients in the trial had no prior chemotherapy for advanced or metastatic disease and received at least two lines of prior endocrine therapy in the metastatic setting. Patients were also eligible if they had received one prior line of endocrine therapy combined with a CDK4/6 inhibitor in the metastatic setting and experienced disease progression within six months of starting 1st-line treatment, or received endocrine therapy as an adjuvant treatment and experienced disease recurrence within 24 months. Patients were stratified based on prior CDK4/6 inhibitor use, HER2 expression and prior taxane use in the non-metastatic setting. Patients in the trial had received a median of two prior lines of endocrine therapy. In the overall trial population, 14.9% of patients in the ENHERTU® group and 19.2% in the chemotherapy group had received one prior line of endocrine therapy. No patients had received prior chemotherapy for metastatic disease. The Primary endpoint was Progression Free Survival (PFS) in the HER2-low patient population as measured by Blinded Independent Central Review (BICR). Key Secondary endpoints included Progression Free Survival (PFS) in the overall trial population (HER2-low and HER2-ultralow), Overall survival (OS) in the HER2-low patient population, Objective Response Rate (ORR), Duration of response (DOR) and Safety. The median duration of follow-up was 18.2 months.

In the primary analysis of this study, results showed that in the HER2-low expression patients, ENHERTU® reduced the risk of disease progression or death by 38%, with a median PFS was 13.2 months in the ENHERTU® group, compared to 8.1 months for chemotherapy (HR=0.62; P<0.0001). For the overall trial population (HER2-low and HER2-ultralow), the median PFS results were similar and the median PFS was 13.2 months for ENHERTU® versus 8.1 months for chemotherapy (HR=0.63; P<0.0001). ENHERTU® reduced the risk of disease progression or death by 37% compared to chemotherapy.

A prespecified exploratory analysis showed that the improvement in PFS was consistent between patients with HER2-low and HER2-ultralow expression. In patients with HER2-ultralow expression, ENHERTU® reduced the risk of disease progression or death by 22% compared to chemotherapy, with a median PFS of 13.2 months versus 8.3 months, respectively (HR=0.78).

The Objective Response Rate (ORR) in HER2-Low Population was 56.5% for ENHERTU® compared to 32.2% for chemotherapy, in the Overall Trial Population was 57.3% for ENHERTU® versus 31.2% for chemotherapy, and in the HER2-Ultralow Subgroup was 61.8% for ENHERTU® versus 26.3% for chemotherapy. The median duration of response across these three groups was 14.3 months.

The safety profile of ENHERTU® was consistent with previous breast cancer clinical trials and no new safety concerns identified. The most common Grade 3 or higher treatment-related adverse events occurring in 5% or more of patients treated with ENHERTU® were neutropenia (20.7%) and anemia (5.8%). Interstitial Lung Disease (ILD), adjudicated as drug-related by an independent committee, occurred in 11.3% of patients treated with ENHERTU®. The majority of ILD events were low grade.

The results from the DESTINY-Breast06 trial underscore the significant clinical benefits of ENHERTU® in improving PFS and ORR in patients with HR-positive, HER2-low, and HER2-ultralow metastatic breast cancer, offering a promising alternative to standard chemotherapy. These findings highlight the potential of ENHERTU® to become a new standard of care for this patient population, pending further investigation and regulatory approval. The detailed positive outcomes underscore the clinical benefits and reinforce the promise of ENHERTU® in treating this challenging cancer subtype.

Trastuzumab Deruxtecan after Endocrine Therapy in Metastatic Breast Cancer. Bardia A, Hu X, Dent R, et al. for the DESTINY-Breast06 Trial Investigators. N Engl J Med 2024;391:2110-2122. DOI: 10.1056/NEJMoa2407086.

RYBREVANT® plus LAZCLUZE® versus TAGRISSO® in Previously Untreated EGFR-Mutated Advanced NSCLC

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SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2024, about 234,580 new cases of lung cancer will be diagnosed and 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histological subtype of lung cancer. Approximately 10-15% of Caucasian patients and 35-50% of Asian patients with Adenocarcinomas, harbor activating EGFR mutations, and 90% of these mutations are either exon 19 deletions or L858R substitution mutation in exon 21.

Epidermal Growth Factor Receptor (EGFR) plays an important role in regulating cell proliferation, survival and differentiation, and is overexpressed in a variety of epithelial malignancies. EGFR targeted Tyrosine Kinase Inhibitors (TKIs) such as Gefitinib, Erlotinib, Afatinib, Dacomitinib and Osimertinib (TAGRISSO®) target the EGFR signaling cascade. However, patients eventually develop drug resistance due to new EGFR mutations. Another important cause of drug resistance to TKIs is due to the activation of parallel RTK (Receptor Tyrosine Kinase) pathways such as Hepatocyte Growth Factor/Mesenchymal-Epithelial Transition factor (HGF/MET) pathway, thereby bypassing EGFR TKI inhibitors. These patients are often treated with platinum-based chemotherapy as the next line of therapy, resulting in a median Progression Free Survival of about 5 months.

Amivantamab (RYBREVANT®) is a fully human bispecific antibody directed against EGFR and MET receptors. Amivantamab binds extracellularly and simultaneously blocks ligand-induced phosphorylation of EGFR and c-MET, inhibiting tumor growth and promoting tumor cell death. Further, Amivantamab down regulates receptor expression on tumor cells thus preventing drug resistance mediated by new emerging mutations of EGFR or c-MET. By binding to the extracellular domain of the receptor protein, Amivantamab can bypass primary and secondary TKI resistance at the active site. Amivantamab also engages effector cells such as Natural Killer cells, monocytes, and macrophages via its optimized Fc domain. Amivantamab demonstrated activity against a wide range of activating and resistance mutations in EGFR-mutated NSCLC, and in patients with MET exon 14 skip mutations, and is approved for the treatment of patients with EGFR exon 20 insertion mutations, whose disease progressed on or after platinum-based chemotherapy.

Lazertinib (LAZCLUZE®) is a highly selective, third-generation TKI that penetrates the CNS, with demonstrated efficacy in activating EGFR mutations and acquired T790M “gatekeeper” point mutation. Combining Amivantamab with Lazertinib has been shown to provide a synergistic benefit by targeting the extracellular and catalytic EGFR domains. The combination of Amivantamab plus Lazertinib has shown clinically meaningful and durable antitumor activity in patients with previously untreated or Osimertinib-pretreated EGFR –mutated advanced NSCLC, with clinical activity against a broad spectrum of secondary EGFR and MET molecular alterations and even in tumors of patients without an identified resistance mechanism.

The MARIPOSA trial is an international, randomized Phase 3 study, conducted to assess the efficacy and safety of a combination of Amivantamab and Lazertinib as compared with Osimertinib alone, as first-line treatment in patients with EGFR-mutated advanced NSCLC. In this study, a third arm evaluated Lazertinib monotherapy, to dissect the individual contributions of each component in the combination. This study included 1074 patients (N=1074) with untreated EGFR-mutated advanced NSCLC who were randomly assigned in a 2:2:1 ratio to receive Amivantamab plus Lazertinib (N=429), Osimertinib monotherapy (N=429), or Lazertinib monotherapy (N=216). Amivantamab was administered weekly at a dose of 1050 mg IV (or 1400 mg IV in patients with a body weight of 80 kg or more) for the first 4 weeks (cycle 1), with the first infusion split over a period of 2 days (with 350 mg given on cycle 1, day 1, and the remainder given on cycle 1, day 2). Starting at cycle 2, the same Amivantamab dose was administered every 2 weeks. Osimertinib 80 mg and Lazertinib 240 mg were taken orally daily. The median age was 63 years, majority of patients were Asian women or White and had never smoked. Approximately 60% had EGFR exon 19 deletions and 40% had exon 21 L858R mutations. Randomization was stratified according to EGFR mutation type (ex19del or L858R), Asian race (yes or no), and history of brain metastases (yes or no). The Primary end point was Progression-Free Survival (PFS) in the Amivantamab plus Lazertinib group as compared with the Osimertinib group, as assessed by Blinded Independent Central Review. Secondary end points included Overall Survival (OS), Objective Response (defined as a Complete or Partial Response), Duration of Response, and Safety.

The median PFS was significantly longer in the Amivantamab plus Lazertinib group at 23.7 months compared to 16.6 months in the Osimertinib group ((HR for progression or death = 0.70; P<0.001). The Objective Response was 86% in the Amivantamab plus Lazertinib group and 85% in the Osimertinib group. Among patients with a confirmed response (336 in the Amivantamab plus Lazertinib group and 314 in the Osimertinib group), the median response duration was 25.8 months and 16.8 months, respectively. In a planned interim Overall Survival analysis, Hazard Ratio for death with Amivantamab plus Lazertinib was 0.80 (95% CI, 0.61–1.05).

EGFR and MET-related toxic effects were the most common side effects and most adverse events were of grade 1 or 2. The treatment discontinuation due to adverse events occurred in 10% of patients in the Amivantamab plus Lazertinib group versus 3% in the Osimertinib group. The incidence of venous thromboembolic adverse events was higher with Amivantamab Plus Lazertinib than with Osimertinib and most of the thromboembolic events in the Amivantamab plus Lazertinib group occurred during the first 4 months of treatment. This has been attributed to a transitory prothrombotic state caused by a mechanism of rapid tumor-cell death by the Amivantamab plus Lazertinib combination.

In conclusion, the combination of Amivantamab plus Lazertinib demonstrated superior efficacy over Osimertinib as a first-line therapy for EGFR-mutated advanced NSCLC, offering longer Progression-Free Survival and Duration of Response.

Amivantamab plus Lazertinib in Previously Untreated EGFR-Mutated Advanced NSCLC. Cho BC, Lu S, Felip E, et al. for the MARIPOSA Investigators. N Engl J Med 2024;391:1486-1498.

FDA Approves IMFINZI® after Chemoradiotherapy in Limited-Stage Small Cell Lung Cancer

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SUMMARY: The FDA on December 4, 2024, approved Durvalumab (IMFINZI®) for adults with Limited Stage-Small Cell Lung Cancer (LS-SCLC) whose disease has not progressed following concurrent platinum-based chemotherapy and radiation therapy. The American Cancer Society estimates that for 2024 about 234,580 new cases of lung cancer will be diagnosed and about 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Small Cell Lung Cancer (SCLC) accounts for approximately 13-15% of all lung cancers and is aggressive. Limited Stage-Small Cell Lung Cancer – LS-SCLC (Stage I-III) accounts for approximately 30% of SCLC diagnoses and the disease is confined to one hemithorax. These patients are often treated with a combination of Carboplatin or Cisplatin with Etoposide and radiotherapy. Despite initial response, LS-SCLC typically recurs and progresses rapidly, and only 15-30% of patients are alive, five years after diagnosis.

Based on the premise that SCLC has a high mutation rate, it was hypothesized that these tumors may be immunogenic, and more recently immunotherapy with checkpoint inhibitors has demonstrated clinical activity in SCLC. Durvalumab (IMFINZI®) is a selective, high-affinity, human IgG1 monoclonal antibody, that blocks the binding of Programmed Death Ligand 1 (PD-L1) to Programmed Death 1 (PD-1) receptor and CD80, thereby unleashing the T cells to recognize and kill tumor cells. Tremelimumab (IMJUDO®) is a human immunoglobulin G2 monoclonal antibody that targets and blocks the activity of CTLA-4, enhancing binding of CD80 and CD86 to CD28. This complimentary mechanisms of action broadens clinical activity, potentially overcoming primary resistance to PD-(L)1 blockade by enabling novel T-cell responses.

The rationale for the ADRIATIC trial was supported by findings from the pivotal Phase III PACIFIC and CASPIAN trial. In the PACIFIC trial, Durvalumab after concurrent chemoradiotherapy for Stage III Non-Small Cell Lung Cancer, improved both Overall Survival (OS) and Progression Free Survival (PFS), whereas in the CASPIAN trial, Durvalumab with Platinum and Etoposide chemotherapy significantly improved OS, compared to chemotherapy alone, in newly diagnosed patients with extensive-stage SCLC.

The ADRIATIC trial is a Phase III, randomized, double-blind, placebo-controlled, multicenter, global study that assessed the efficacy and safety of Durvalumab as consolidation therapy in patients with Limited-Stage Small Cell Lung Cancer (LS-SCLC) who had not progressed after concurrent platinum-based chemoradiotherapy. This trial randomized 730 patients with Stage I to III LS-SCLC, including those with inoperable Stage I/II disease. Eligible patients had a WHO Performance Status of 0 or 1 and had not experienced disease progression after completing concurrent chemoradiotherapy. Chemotherapy consisted of a combination of Platinum plus Etoposide for up to 4 cycles, and the radiation therapy could either be once daily up to 66 Gy, or twice a day up to 45 Gy. Prophylactic Cranial Irradiation (PCI) was allowed before randomization. Patients were randomized within 6 weeks after completing concurrent chemoradiotherapy to experimental arms Durvalumab monotherapy 1500 mg IV every 4 weeks with or without Tremelimumab 75 mg IV every 4 weeks for up to 4 cycles each, followed by Durvalumab every four weeks for up to 24 months or Placebo every 4 weeks. There was a protocol amendment in November 2020, and patients were randomly assigned in a 1:1 ratio to the Durvalumab group or placebo group only. Baseline characteristics and prior treatment were well balanced between groups. The median age was 62 years and 87% of patients had Stage III disease at diagnosis. This analysis compared the outcomes in patients assigned to receive Durvalumab monotherapy (N=264) with patients who received placebo (N=266). The dual Primary endpoints were Progression Free Survival (PFS) and Overall Survival (OS) for Durvalumab monotherapy versus placebo. Key Secondary endpoints included OS and PFS for Durvalumab plus Tremelimumab versus placebo, Safety, and Quality of Life measures. The median duration of follow-up for OS and PFS in censored patients at this first planned interim analysis was 37.2 and 27.6 months, respectively.

Durvalumab demonstrated a statistically significant improvement in OS compared to placebo (HR=0.73; P=0.01), translating to a 27% reduction in the risk of death. The estimated median OS with Durvalumab was 55.9 months, compared to 33.4 months with placebo. The 24-month OS rate was 68% with Durvalumab versus 58.5% with placebo, and the 36-month OS rate was 56.5% versus 47.6%, respectively. The median PFS was 16.6 months with Durvalumab versus 9.2 months with placebo, representing a 24% reduction in the risk of disease progression or death (HR=0.76; P=0.02). The 18-month PFS rate was 48.8% with Durvalumab versus 36.1% with placebo, and the 24-month PFS rate was 46.2% with Durvalumab versus 34.2% with placebo. Treatment benefit was generally consistent across predefined patient subgroups for both OS and PFS. Grade 3/4 Adverse Events (AEs) were similar in both treatment groups at 24.3%, but treatment discontinuation due to AEs was slightly higher in the Durvalumab arm (16.3% versus 10.6% in the placebo arm). Any grade pneumonitis was reported in 38.0% of patients in the Durvalumab arm compared to 30.2% in the placebo arm.

The results of the ADRIATIC trial represent a significant advancement in the treatment of Limited Stage-Small Cell Lung Cancer (LS-SCLC). Durvalumab consolidation therapy demonstrated a statistically significant and clinically meaningful improvement in both OS and PFS compared to placebo. These findings support Durvalumab as a new standard of care for patients with LS-SCLC following concurrent chemoradiotherapy, potentially changing the treatment landscape for this aggressive disease.

Durvalumab after Chemoradiotherapy in Limited-Stage Small-Cell Lung Cancer. Cheng Y, Spigel DR, Cho BC, et al. for the ADRIATIC Investigators. N Engl J Med 2024;391:1313-1327.

Stockholm3 Blood Test Identifies Aggressive Prostate Cancer

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SUMMARY: Prostate cancer is the most common cancer in American men with the exclusion of skin cancer, and 1 in 8 men will be diagnosed with prostate cancer during their lifetime. It is estimated that in the United States, about 299,010 new cases of prostate cancer will be diagnosed in 2024 and 35,250 men will die of the disease.

PSA (Prostate Specific Antigen) is one of the most widely used prostate cancer biomarkers, and the widespread use of PSA testing in the recent years has resulted in a dramatic increase in the diagnosis and treatment of prostate cancer. The management of clinically localized prostate cancer that is detected based on PSA levels remains controversial, and management strategies for these patients have included Surgery, Radiotherapy or Active Monitoring. However, it has been proposed that given the indolent nature of prostate cancer in general, majority of the patients do not benefit from treatment intervention and many patients die of competing causes. PSA test CANNOT distinguish between aggressive and benign cancer. As a result, many men have to undergo unnecessary follow-ups with a biopsy of the prostate. Further, treatment intervention can result in adverse effects on sexual, urinary, or bowel function. PSA test is also difficult to interpret, and PSA elevation can be associated with several non-malignant conditions such as older age, infection, inflammation and Benign Prostatic Hypertrophy. The U.S. Preventive Services Task Force (USPSTF) has recommended that population screening for prostate cancer with PSA should not be adopted as a public health policy, because the risks appeared to outweigh benefits, from detecting and treating PSA-detected prostate cancer.

Stockholm3 is a blood test that combines 5 protein biomarkers, 101 genetic markers, and clinical data with an advanced algorithm, in order to detect almost 100% of aggressive prostate cancers at an early stage. The Stockholm3 test provides an answer that can be negative or positive. A negative answer represents low or normal risk of developing prostate cancer, whereas referral to an urologist is recommended if the test is positive. The Stockholm3 test has been validated in over 75, 000 men and has been used in health systems in Sweden, Norway, Finland, Germany, Switzerland, UK and Turkey, and results have been published in international peer-reviewed journals. Evidence suggests that Stockholm3 is more effective at predicting risk than PSA testing alone, for men aged 45-74 with PSA of at least 1.5ng/ml. Several studies have shown that the application of this test can reduce the number of biopsies by 32%, without compromising the diagnostic capacity of intermediate grade prostate cancers (Gleason 7 or higher), in comparison with the use of the PSA value 3 ng/ mL as cut-off value for biopsy recommendation. However, none of the validation studies included ethnically diverse population.

SEPTA is a prospective trial conducted to validate Stockholm3 in an ethnically diverse population, for prostate cancer risk stratification, and determine whether it could achieve noninferior sensitivity and superior specificity in this diverse population. This trial included men who were referred for prostate biopsy at North American sites from 2019 to 2023. Study participants had no previous diagnosis of prostate cancer. This study also used bio-banked specimens from 2008 to 2020. The cohort comprised 912 enrolled men and 1,217 with bio-banked blood. The median age was 63 years, 46% were White, 24% Black, 16% Asian and 14% were Hispanic.

This trial had 2 prespecified Primary goals: 1) Demonstrate noninferiority of the test in detecting Clinically Significant Prostate Cancer (defined as Gleason Grade group 2 or more), compared to PSA testing. 2) Prove superior specificity of the test versus PSA testing, thereby reducing the number of biopsies in men with benign or Gleason Grade group 1 biopsies. A Secondary goal was to evaluate Stockholm3 and PSA across ethnic subgroups. The study assessed Stockholm3 performance using prespecified thresholds and compared it to PSA across different ethnic subgroups. Statistical analysis plans were established before data analysis.

It was noted that the median PSA and Stockholm3 values among the participants were 6.1 ng/mL and 17, respectively. A total of 16% underwent MRI-targeted biopsies, and 20% had a prior benign biopsy. On biopsy, 29% were diagnosed with Clinically Significant Prostate Cancer, 14% with Gleason Grade group 1 cancer, and 57% with benign findings. The detection rate for Clinically Significant Prostate Cancer varied across ethnic groups: African American/Black (37%), White/Caucasian (28%), Hispanic/Latino (29%), and Asian (21%).

Overall, Stockholm3 value 15 or higher demonstrated noninferiority to a PSA value of 4 ng/mL or higher and nearly three times superior specificity. These results were consistent across ethnic subgroups. The researchers noted that using a Stockholm3 value of 15 or higher would have reduced benign and Gleason Grade group 1 biopsies by 45% overall and between 42-52% across ethnic subgroups, compared to PSA of 4 ng/ml or higher.

The study concluded that in an ethnically diverse population, Stockholm3 could significantly reduce unnecessary biopsies and diagnoses of low-grade tumors, while maintaining similar sensitivity to PSA, for detecting Clinically Significant Prostate Cancer. The results suggest that
Stockholm3 could improve risk stratification and reduce harms associated with prostate cancer screening in diverse populations.

Stockholm3 in a Multiethnic Cohort for Prostate Cancer Detection (SEPTA): A Prospective Multicentered Trial. Vigneswaran HT, Eklund M, Discacciati A, et al. on behalf of the SEPTA STHLM3 Study Group. J Clin Oncol. 2024;42:3806-3816. DOI:10.1200/JCO.24.00152.

TAGRISSO® after Chemoradiotherapy in Stage III EGFR-Mutated NSCLC

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SUMMARY: The FDA on September 25, 2024, approved Osimertinib (TAGRISSO®) for adult patients with locally advanced, unresectable (Stage III) Non-Small Cell Lung Cancer (NSCLC) whose disease has not progressed during or following concurrent or sequential platinum-based chemoradiation therapy and whose tumors have EGFR exon 19 deletions or exon 21 L858R mutations, as detected by an FDA-approved test. Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2024, about 234,580 new cases of lung cancer will be diagnosed and 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Approximately one third of all patients with NSCLC have Stage III, locally advanced disease at the time of initial presentation and 60 to 90% of these patients have unresectable disease. These patients are treated with concurrent chemoradiotherapy (CRT) followed by consolidation therapy with Durvalumab (IMFINZI®) in patients without progression, as this regimen confers an Overall Survival advantage, and is considered the standard of care (PACIFIC trial).

EGFR (Epidermal Growth Factor Receptor) mutations are found in up to one third of patients with unresectable Stage III NSCLC. There are currently no approved targeted treatments for patients with unresectable Stage III EGFR-mutated NSCLC. The current standard of care, which includes consolidation therapy with Durvalumab, may not offer clear benefits to this subset of patients with EGFR mutations.

Osimertinib (TAGRISSO®) is a highly selective third-generation, irreversible Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor (TKI), presently approved by the FDA, for the first-line treatment of patients with metastatic NSCLC, whose tumors have Exon 19 deletions or Exon 21 L858R mutations, as well as treatment of patients with metastatic EGFR T790M mutation-positive NSCLC, whose disease has progressed on or after EGFR-TKI therapy. Osimertinib is also approved by the FDA as adjuvant treatment for resected Stage IB–IIIA EGFR-mutated NSCLC. Further, Osimertinib has higher CNS penetration and is therefore able to induce responses in 70-90% of patients with brain metastases.

LAURA was a global, randomized, double-blind, placebo-controlled, multicenter Phase III trial conducted to assess the efficacy and safety of Osimertinib in patients with unresectable Stage III NSCLC harboring EGFR mutations (EGFR exon 19 deletion or exon 21 L858R mutation). The trial enrolled patients who had not experienced disease progression during or after definitive platinum-based chemoradiotherapy (CRT). A total of 216 patients who had undergone CRT were randomly assigned 2:1 to receive Osimertinib 80 mg orally once daily (N=143) or placebo once per day (N=73). Treatment was continued until Blinded Independent Central Review (BICR)–assessed disease progression, unacceptable toxicity, or other discontinuation criteria were met. Upon disease progression, patients in the placebo arm were permitted to receive Osimertinib, allowing for crossover therapy. Stratification factors included method of CRT (concurrent versus sequential) and disease Stage (IIIA versus IIIB/C). Both treatment groups were well balanced. The median patient age was 63 years, approximately 60% of participants were female, 83% were Asian, 69% had never smoked and 85% had Stage IIIA and B disease. Majority of patients received concurrent CRT rather than sequential CRT. The Primary end point was Progression Free Survival (PFS) as assessed by BICR. Key Secondary end points included Overall Survival (OS), survival without progression of CNS disease (CNS Progression Free Survival), Objective Response Rate (ORR), Duration of Response, Quality of Life, and Safety.

Treatment with Osimertinib resulted in significant PFS improvement compared to placebo. The median PFS was 39.1 months in the Osimertinib group versus 5.6 months in the placebo group, representing an 84% reduction in the risk of disease progression or death (HR=0.16; P<0.001). Additionally, a higher percentage of patients in the Osimertinib group remained alive and progression-free at 12 months compared to the placebo group (74% versus 22% respectively). Subgroup analyses were conducted to evaluate the consistency of treatment effects across various demographic and clinical factors. The benefits of Osimertinib were observed across all prespecified subgroups, indicating a consistent treatment effect, regardless of patient characteristics. The incidence of new lesions was lower with Osimertinib compared to placebo (22% versus 68%), and this included new brain lesions (8% versus 29%) and new lung lesions (6% versus 29%) respectively. The Objective Response Rate was higher with Osimertinib than with placebo (57% versus 33%). The median Duration of Response was longer with Osimertinib (36.9 months) than with placebo (6.5 months). Interim OS data showed a favorable trend for Osimertinib, although maturity was limited at the time of analysis. Further follow-up will be conducted to assess OS as a secondary endpoint. The adverse event profile of Osimertinib was generally consistent with previous studies. Grade 3 or higher adverse events occurred more frequently in the Osimertinib group, with radiation pneumonitis being the most common. However, no new safety concerns emerged during the trial.

In summary, treatment with Osimertinib resulted in significantly longer Progression Free Survival than placebo in patients with unresectable Stage III EGFR-mutated NSCLC following definitive CRT, and should be considered the new standard of care for this group of patients. Overall, the LAURA study represents a major breakthrough in the treatment of EGFR-mutated Stage III NSCLC, addressing an unmet need for targeted therapies in this setting. Further follow-up will provide additional insights into the long-term efficacy and safety of Osimertinib in this patient population.

Osimertinib after Chemoradiotherapy in Stage III EGFR-Mutated NSCLC. Lu S, Kato T, Dong X, et al. for the LAURA Trial Investigators. N Engl J Med. 2024;391:585-597.

FDA Grants Accelerated Approval to ZIIHERA®for Metastatic HER2-Positive Biliary Tract Cancer

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SUMMARY: The FDA on November 20, 2024, granted accelerated approval to Zanidatamab-hrii (ZIIHERA®), a bispecific HER2-directed antibody, for previously treated, unresectable or metastatic HER2-positive (IHC 3+) Biliary Tract Cancer (BTC), as detected by an FDA-approved test. The FDA simultaneously also approved VENTANA PATHWAY anti-HER-2/neu (4B5) Rabbit Monoclonal Primary Antibody as a companion diagnostic device to aid in identifying patients with BTC who may be eligible for treatment with Zanidatamab.

Biliary Tract Cancer (Cholangiocarcinoma) is a rare and highly aggressive heterogenous cancer and is the second most common type of primary liver cancer after Hepatocellular carcinoma. It comprises about 30% of all primary liver tumors and includes both intrahepatic and extrahepatic bile duct cancers. It is estimated that approximately 211,000 patients are diagnosed with Biliary Tract Cancer and 174,000 patients will die of the disease each year globally. Biliary Tract Cancer is most frequently diagnosed in patients between 50 to 70 years old, and 75% of patients are diagnosed at an advanced stage. BTCs consist of intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma, gallbladder cancer, and Ampulla of Vater cancer. Klatskin tumor is a type of Cholangiocarcinoma that begins in the hilum, at the junction of the left and right bile ducts. It is the most common type of Cholangiocarcinoma, accounting for more than half of all cases. About 8,000 people in the US are diagnosed with Cholangiocarcinoma each year and approximately 20% of the cases are suitable for surgical resection. Patients diagnosed with Biliary Tract Cancer have a very poor prognosis, and the 5-year survival among those with advanced stage disease is less than 10%, with limited progress made over the past two decades. There is therefore an urgent unmet need for new effective therapies. Patients with advanced Biliary Tract cancers often receive chemotherapy in the first and second line settings, with limited benefit. Gemcitabine and Cisplatin combination is currently the first line standard-of-care treatment.

BTCs are heterogenous and thus their pathogenesis and genomic drivers may vary. HER2 overexpression or gene amplification is one of the genomic drivers and HER2 overexpression rates vary depending on the anatomic origin of the Biliary Tract Cancer. Extrahepatic cholangiocarcinoma has a higher rate of HER2 overexpression (about 16-18%), compared to intrahepatic cholangiocarcinoma (about 5%), and about 10-16% for gallbladder cancers, making HER2 a potential therapeutic target in a vast majority of these patients.

Zanidatamab is a novel HER2-targeted, humanized, immunoglobulin G1 (IgG1), bispecific monoclonal antibody, that targets two distinct non-overlapping extracellular domains of HER2, ECD2 and ECD4 (biparatopic binding). This results in dual HER2 signal blockade, HER2 clustering, receptor internalization, and downregulation. This inhibits HER2 activation, HER2-mediated signaling and HER2-mediated tumor cell growth. The specific binding of Zanidatamab to tumor cells and HER2 aggregation also activates various immune-mediated responses, including Complement-Dependent Cytotoxicity (CDC), Antibody-Dependent Cellular Cytotoxicity (ADCC), and Antibody-Dependent Cellular Phagocytosis (ADCP) against tumor cells that overexpress HER2. Zanidatamab binds to HER2-expressing tumor cells with greater antibody saturation than Trastuzumab or Pertuzumab.

The present FDA approval was based on data from HERIZON-BTC-01 (NCT04466891), a pivotal Phase 2b, open-label, multicenter, single-arm trial, that evaluated the efficacy and safety of Zanidatamab in patients with HER2-positive BTC. This study included 87 patients with unresectable or metastatic HER2-positive BTC, and all patients received at least one prior Gemcitabine-containing regimen in the advanced disease setting. The median age was 64 years, 54% were women, 66% were Asian, 52% had gallbladder cancer, 30% had intrahepatic cholangiocarcinoma and 18% had extrahepatic cholangiocarcinoma. Patients received Zanidatamab at 20 mg/kg IV every two weeks in 28-day cycles.
Patients were assigned to one of two cohorts based on immunohistochemistry (IHC) status.
Cohort 1 (HER2-positive): Patients with IHC 3+ or IHC 2+ disease (N=80 total, including 62 with IHC 3+).
Cohort 2 (HER2-negative): Patients with IHC 0 or 1+ disease (N=7).
The major efficacy outcome measures were Objective Response Rate (ORR) and Duration of Response (DOR) as determined by an Independent Central Review.

Among the 62 patients with IHC3+ status per central assessment, the ORR was 52% and the median DOR was 14.9 months. The median Overall Survival was 18.1 months for IHC 3+ patients and 5.2 months for IHC 2+ patients. Common treatment related adverse events included diarrhea, infusion related reactions, nausea, vomiting, fatigue, and elevated liver enzymes. Treatment discontinuation rate was 2.3%.

In conclusion, the approval of Zanidatamab represents a significant advancement in the management of HER2-positive BTC and a critical unmet need. A Phase 3 trial is planned to evaluate Zanidatamab in the first-line setting for metastatic BTC.

Zanidatamab in previously-treated HER2-positive (HER2+) biliary tract cancer (BTC): Overall survival (OS) and longer follow-up from the phase 2b HERIZON-BTC-01 study. Pant S, Fan J, Oh D-Y, et al. J Clin Oncol. 2024;42(suppl 16):4091. doi:10.1200/JCO.2024.42.16_suppl.4091.

FDA Approves REVUFORJ® for Acute Leukemia with KMT2A Translocation

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SUMMARY: The FDA on November 15, 2024, approved Revumenib (REVUFORJ®), a menin inhibitor, for Relapsed or Refractory acute leukemia with a lysine methyltransferase 2A gene (KMT2A) translocation in adult and pediatric patients 1 year and older. The American Cancer Society estimates that in 2024, 20,800 new cases of Acute Myeloid Leukemia (AML) will be diagnosed in the United States and 11,220 patients will die of the disease. AML is one of the most common types of leukemia in adults and can be considered as a group of molecularly heterogeneous diseases with different clinical behavior and outcomes. A significant percentage of patients with newly diagnosed AML are not candidates for intensive chemotherapy or have disease that is refractory to standard chemotherapy. Even with the best available therapies, the 5-year Overall Survival in patients 65 years of age or older is less than 5%. Cytogenetic analysis has been part of routine evaluation when caring for patients with AML. By predicting resistance to therapy, tumor cytogenetics will stratify patients based on risk, and help manage them accordingly. Even though cytotoxic chemotherapy may lead to long term remission and cure in a minority of patients with favorable cytogenetics, patients with high-risk features such as unfavorable cytogenetics, molecular abnormalities, prior myelodysplasia, and advanced age, have poor outcomes with conventional chemotherapy alone. More importantly, with the understanding of molecular pathology of AML, personalized and targeted therapies are becoming an important part of the AML treatment armamentarium. Over 50% of AML cases lack targetable mutations, relying instead on toxic chemotherapy.

Rearrangements of KMT2A gene previously known as MLL are found in 80% of infant Acute Lymphoblastic Leukemia (ALL) and in 5-15% of acute leukemia cases in children and adults, including myeloid, lymphoid, or mixed phenotypes. NPM1 mutations are the most common genetic alteration in adult Acute Myeloid Leukemia (AML), occurring in up to 30% of cases. Acute leukemias with KMT2A rearrangements have a poor prognosis, with a 5-year overall survival rate of less than 25%. There are no targeted therapies currently approved specifically for acute leukemia with KMT2A gene rearrangements or NPM1 mutations. Both KMT2A gene rearrangements and NPM1 mutations cause blood cells to regress to a stem-cell-like state, leading to the formation of leukemia cells. For leukemias driven by KMT2A gene rearrangements and NPM1 mutations, menin is a critical oncogenic cofactor. Menin interacts with the protein MLL1 (produced by KMT2A), forming a menin–MLL1 complex. This complex binds to chromatin and activates aberrant gene pathways, specifically HOX genes and their cofactor MEIS1, critical for leukemia development.

Revumenib is a potent, oral, small molecule menin inhibitor. It blocks the menin–MLL1 interaction, preventing the formation of the menin–MLL1 complex. By disrupting this complex, Revumenib stops the aberrant activation of HOX and MEIS1 gene expression and allows leukemia cells to either die or differentiate back into normal blood cells. Unlike other targeted therapies that block dysfunctional proteins, Revumenib prevents aberrant gene expression at its source. Its ability to target a common mechanism in AML makes it broadly applicable. Preclinical Studies demonstrated that menin inhibition reverses leukemia progression by downregulating HOX and MEIS1 transcription disrupting oncogenic complexes formed by either option for patients with KMT2A gene arrangements or NPM1-mutated AML. Revumenib showed dramatic antileukemic activity, making this agent promising.

AUGMENT-101 is a single-arm cohort of an open-label, multicenter trial which included 104 adult and pediatric patients (at least 30 days old) with Relapsed or Refractory (R/R) acute leukemia with a KMT2A translocation. Eligible patients had a corrected QT interval of less than 450 milliseconds and those with an11q23 partial tandem duplication were excluded. Revumenib was administered at a dose that was approximately equivalent to 160 mg in adults orally twice daily. Treatment was continued until progressive disease, unacceptable toxicity, failure to achieve a morphological leukemia-free state by 4 cycles of treatment, or Hematopoietic Stem Cell Transplantation (HSCT). The median patient age was 37 years, 83% of patients had AML, 15% had Acute Lymphoblastic Leukemia, and 2% had mixed phenotype acute leukemia. Approximately 59% had relapsed/refractory disease, 21% had primary refractory disease, 20% of patients had untreated relapsed disease and 44% of patients underwent prior HSCT. The main efficacy outcome measures were Complete Remission (CR) plus CR with partial hematologic recovery (CRh), the duration of CR plus CRh, and conversion from transfusion dependence to independence.

The CR plus CRh rate was 21.2%, and the median CR plus CRh duration was 6.4 months. Of the 22 patients achieving CR or CRh, the median time to CR or CRh was 1.9 months. Among the 83 patients dependent on RBC and/or platelet transfusions at baseline, 14% became independent of RBC and platelet transfusions during any 56-day post-baseline period. Of the 21 patients independent of both RBC and platelet transfusions at baseline, 48% remained transfusion independent during any 56-day post-baseline period. The most common adverse reactions noted in this study were hemorrhage, nausea, increased phosphate, musculoskeletal pain, neutropenia, infection, elevated liver enzymes, differentiation syndrome, QT prolongation and fatigue.

It was concluded that Revumenib is the first menin inhibitor and its efficacy represents a substantial improvement over previously available therapies, and represents a major breakthrough for patients with Relapsed or Refractory acute leukemia with a KMT2A translocation.

https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-revumenib-relapsed-or-refractory-acute-leukemia-kmt2a-translocation

Early Detection of Pancreatic Cancer with an Exosome-Based Liquid Biopsy

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SUMMARY: The American Cancer Society estimates that in 2024, about 66,440 people will be diagnosed with pancreatic cancer and 51,750 people will die of the disease. Detecting cancer at early stages can significantly increase survival rates and outcomes.

Several multi-cancer early detection tests are being developed that involve blood-based circulating cell-free tumor DNA (cfDNA) in the plasma, to track hundreds of patient-specific mutations, to detect Minimal Residual Disease (MRD) , as well as detection of abnormal methylation patterns, followed by machine learning approaches, to differentiate between cancer and non-cancer for detecting clinically significant, late-stage (III and IV) cancers. Early detection of cancer, however, is the key to improving survival. This is particularly relevant for certain cancer types. Pancreatic Ductal AdenoCarcinoma (PDAC) is one of the deadliest cancers, and a leading cause of all cancer-related deaths in the United States and is typically detected when the disease is advanced. However, when detected at Stage I, survival rates can be as high as 80%. Even though serum CA19-9 is intended as an aid in the management of patients with confirmed pancreatic cancer for serial monitoring of their response to therapy and disease progression, it is NOT recommended by the FDA for screening, as it may be elevated in several benign conditions. Currently, there are no general screening strategies to detect asymptomatic, early-stage PDAC and there is therefore a significant unmet need in this patient group.

Exosomes are 30-150 nm-sized Extracellular Vesicles (EVs) secreted by multiple different cell types and released by tumors into the bloodstream. They mediate intercellular signaling by shuttling mRNAs and microRNAs between distant cells and tissues and therefore carry functional protein biomarkers representing the tumor proteome. MicroRNAs play a role in regulating gene expression and have been implicated in various cancer types due to their stability and specific expression patterns associated with tumor presence. Exosomes retain the cytoplasmic content of the cell from which they were shed, essentially replicating the biology of their tissue of origin. Exosomes represent one potential approach for more sensitive detection of cancer-related biomarkers from blood.

The researchers developed an exosome-based liquid biopsy signature as a diagnostic tool to detect pancreatic cancer through the analysis of circulating biomarkers in blood samples. This signature utilizes two primary types of biomarkers – Eight microRNAs unique to exosomes shed from pancreatic cancer cells, combined with five cell-free DNA (cfDNA) markers such as mutations or alterations in DNA methylation patterns found in the blood of patients with pancreatic cancer.

In previous work, researchers had tested an exosome-based liquid biopsy signature on a cohort of 95 individuals from either the United States or Japan. This initial study reported an impressive 98% detection rate for pancreatic cancer. Building on this success, the latest research aimed to validate this liquid biopsy approach in larger, more diverse populations across multiple institutions and countries.

The most recent study involved a comprehensive, multi-cohort evaluation to assess the performance of the exosome-based liquid biopsy signature. The study enrolled participants from four countries, each contributing both pancreatic cancer patients and healthy donors:
• Japan: 150 individuals with pancreatic cancer and 102 healthy donors
• United States: 139 individuals with pancreatic cancer and 193 healthy donors
• South Korea: 184 individuals with pancreatic cancer and 86 healthy donors
• China: 50 individuals with pancreatic cancer and 80 healthy donors

The research methodology involved training the liquid biopsy signature using data from the Japanese cohort. Machine learning algorithms were likely used to train and validate the diagnostic model, optimizing its sensitivity and specificity. After training the signature on the Japanese cohort, the researchers validated its performance using data from cohorts in the United States, South Korea, and China. Each of these cohorts included a mix of pancreatic cancer patients and healthy controls, allowing for an assessment of the signature’s performance across diverse populations.

The performance of the liquid biopsy signature across different cohorts was as follows:
• United States Cohort: The test detected 93% of pancreatic cancers.
• South Korean Cohort: The test detected 91% of pancreatic cancers.
• Chinese Cohort: The test detected 88% of pancreatic cancers.

These validation results demonstrated the signatures robustness and effectiveness in detecting pancreatic cancer across different ethnic and geographic backgrounds, although there was a noted decrease in detection rates with different cohorts.

To enhance the diagnostic accuracy, the researchers combined their exosome-based signature with the traditional pancreatic cancer marker CA 19-9, a carbohydrate antigen often elevated in pancreatic cancer but is less sensitive for detecting early-stage disease. The combination of the exosome-based signature with CA 19-9 improved the detection rate of early-stage pancreatic cancers (Stage I and II) to 97% in the U.S. cohort. This suggests that the combination approach offers a more comprehensive evaluation than CA 19-9 alone.

In conclusion, the exosome-based liquid biopsy signature represents a significant advancement in the early detection of pancreatic cancer. By leveraging the unique properties of exosomal microRNAs and cfDNA, the researchers have developed a diagnostic tool with high sensitivity and specificity. The successful validation in multiple cohorts underscores its potential utility in clinical practice. This assay may be helpful for early detection of pancreatic cancer in certain groups with a high risk for pancreatic cancer such as a family history of pancreatic cancer, germline BRCA mutations, new-onset diabetes, chronic pancreatitis or pancreas precancer lesion such as intraductal papillary mucinous neoplasm. However, addressing the limitations and further optimizing the technology will be crucial for its widespread adoption and effectiveness in diverse populations.

An exosome-based liquid biopsy for non-invasive, early detection of patients with pancreatic ductal adenocarcinoma: A multicenter and prospective study. Xu C, Xu Y, Han H, et al. AACR Annual Meeting 2024. Abstract 3899. Presented April 8, 2024.

FDA Grants Accelerated Approval to SCEMBLIX® for Newly Diagnosed Chronic Myeloid Leukemia

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SUMMARY: The FDA on October 29, 2024, granted accelerated approval to Asciminib (SCEMBLIX®), for adult patients with newly diagnosed Philadelphia Chromosome-positive Chronic Myeloid Leukemia (CML) in chronic phase. The American Cancer Society estimates that about 9,280 new CML cases will be diagnosed in the United States in 2024 and about 1,280 patients will die of the disease. Chronic Myeloid Leukemia constitutes about 15% of all new cases of leukemia and the average age at diagnosis of CML is around 64 years. The hallmark of CML, the Philadelphia Chromosome (Chromosome 22), is a result of a reciprocal translocation between chromosomes 9 and 22, wherein the ABL gene from chromosome 9 fuses with the BCR gene on chromosome 22. As a result, the auto inhibitory function of the ABL gene is lost and the BCR-ABL fusion gene is activated resulting in cell proliferation and leukemic transformation of hematopoietic stem cells.

The Tyrosine Kinase Inhibitors (TKIs) approved for newly diagnosed chronic phase CML in the United States share the same therapeutic target, which is the ATP-binding site of BCR-ABL1 kinase. They include first-generation TKI Imatinib (GLEEVEC®) or second-generation TKIs Nilotinib (TASIGNA®), Dasatinib (SPRYCEL®), or Bosutinib (BOSULIF®). Imatinib is associated with lower patient response and a higher incidence of disease progression than those with second-generation TKIs, whereas treatment with second-generation TKIs can result in faster, deeper molecular responses than Imatinib in frontline therapy, but are associated with more adverse events, necessitating dose modifications and switching treatments. Further, close to 50% of clinical resistance is associated with the acquisition of mutations in this region of the kinase, resulting in conformational changes that render TKIs inactive. Therefore, resistance to one of the TKIs, will likely result in resistance to the others as well. Further, the “gatekeeper” T315I mutation, which has been reported in 20% of patients with mutations, confers resistance to all clinically available TKIs except Ponatinib (ICLUSIG®). There is therefore an unmet need for safe and effective frontline therapy for patients with newly diagnosed chronic phase CML

Asciminib (SCEMBLIX®) is a novel, first-in-class, potent and specific, oral BCR-ABL1 inhibitor that does not bind to the ATP-binding site of the kinase. Instead, it specifically targets the ABL1 myristoyl pocket, also known as a STAMP (Specifically Targeting the ABL Myristoyl Pocket) inhibitor, with activity against native unmutated BCR-ABL1, and all clinically observed ATP-site mutants, including T315I. In a Phase I study, Asciminib was active in heavily pretreated patients with CML who had resistance to or unacceptable side effects from TKIs, including patients in whom Ponatinib had failed, and those with a T315I mutation.

Asciminib was previously approved by the FDA in the US for the treatment of adults with Philadelphia Chromosome positive chronic phase CML who have previously been treated with two or more TKIs. It is also approved in patients with Philadelphia Chromosome positive chronic phase CML with the T315I mutation.

The ASC4FIRST study is a pivotal Phase III, multi-center, open-label, randomized trial aimed at evaluating the efficacy and safety of Asciminib compared to investigator-selected Tyrosine Kinase Inhibitors (TKIs) in adult patients with newly diagnosed Philadelphia chromosome positive Chronic Myeloid Leukemia in chronic phase (CML-CP). A total of 405 patients were enrolled and were randomly assigned in a 1:1 ratio to receive either Asciminib 80 mg orally once daily (N=201) or investigator-selected TKIs which included Imatinib and second generation TKIs such as Bosutinib, Dasatinib or Nilotinib given at approved doses (N=204). Before randomization, investigators, after discussing with patients, selected a TKI (either Imatinib or one of the second-generation TKIs a patient would take, if randomly assigned to the comparator group-prerandomization selected TKI), considering treatment goals, disease and patient characteristics, and coexisting conditions. Randomization was stratified by European Treatment and Outcome Study long-term survival score category (low, intermediate, or high risk), and by TKI selected by investigators before randomization. The two Primary objectives of this study were to compare the efficacy of Asciminib with that of investigator-selected TKIs (all members of this class considered together as a group), and to compare the efficacy of Asciminib with that of Imatinib. Asciminib was not compared with second-generation TKIs as a primary objective. The Primary end point for both objectives was Major Molecular Response (defined as BCR/ABL1 transcript levels 0.1% or less on the International Scale at week 48 that did not meet any treatment failure criteria). The Secondary objective of this study was assessment of Major Molecular Response (MMR) at week 48 with Asciminib, as compared with investigator-selected TKIs among patients with second-generation TKIs as their prerandomization-selected TKI. The median follow-up was 16.3 months in the Asciminib group and 15.7 months in the investigator-selected TKI group.

At the 48-week mark, Asciminib demonstrated a significantly higher MMR rate compared to investigator-selected TKIs (67.7% versus 49.0%; P<0.001). Deep molecular response rates (BCR/ABL1 transcript levels 0.01% or less, were also superior in the Asciminib group compared to investigator-selected TKIs (38.8% versus 20.6%). Patients preselected for Imatinib who were randomized to Asciminib achieved an MMR rate of 69.3% compared to 40.2% in the Imatinib group (P<0.001). Among those preselected for second-generation TKIs, the MMR rate was 66.0% for Asciminib versus 57.8% for the second-generation TKI group.

Asciminib exhibited a favorable safety profile with fewer Grade 3 or higher Adverse Events and lower rates of treatment discontinuation due to Adverse Events. Grade 3 or higher Adverse Events for Asciminib was 38%, for Imatinib was 44.4% and for second-generation TKIs was 54.9%. Discontinuation due to Adverse Events for Asciminib was 4.5%, for Imatinib was 11.1% and for Second-generation TKIs was 9.8%.

It was concluded that Asciminib is the only agent to demonstrate superiority over investigator selected standard-of-care TKIs in achieving higher MMR rates at 48 weeks in newly diagnosed chronic phase CML patients, alongside a better safety and tolerability profile. These findings indicate that Asciminib could significantly improve the treatment landscape for this group of patients, offering hope for better disease control and quality of life, thereby addressing key unmet needs in CML management.

Asciminib in Newly Diagnosed Chronic Myeloid Leukemia. Hochhaus A, Wang J, Kim DD, et al. for the ASC4FIRST Investigators. N Engl J Med 2024;391:885-898.

Adjuvant TAFINLAR® plus MEKINIST® in Stage III Melanoma – 10 Year Follow up

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SUMMARY: The American Cancer Society estimates that for 2024, about 100,640 new cases of melanoma of the skin will be diagnosed in the United States and 8,290 people are expected to die of the disease. The rates of melanoma have been rising rapidly over the past few decades, but this has varied by age. Surgical resection with a curative intent is the standard of care for patients with early-stage melanoma.

Patients with resected Stage IIB/C disease comprise a significant group of patients at significant risk of recurrence. Patients with Stage IIB disease have primary tumors that are more than 2 mm, and 4 mm or less in thickness, with ulceration (T3b), or more than 4 mm in thickness without ulceration (T4a). Patients with Stage IIC disease have primary tumors more than 4 mm in thickness with ulceration (T4b). Although Stage II melanoma is less advanced than Stage III, the 5-year risk of recurrence in patients with Stage IIB or Stage IIC disease without adjuvant therapy is approximately 35% and 50% respectively. The 5-year Melanoma-Specific Survival (MSS) rates for patients with Stage IIB/IIC disease are similar to those for Stage IIIA, Stage IIIB and Stage IIIC disease.

The Mitogen-Activated Protein Kinase pathway (MAPK pathway) is an important signaling pathway which enables the cell to respond to external stimuli. This pathway plays a dual role, regulating cytokine production and participating in cytokine dependent signaling cascade. The MAPK pathway of interest is the RAS-RAF-MEK-ERK pathway. The RAF family of kinases includes ARAF, BRAF and CRAF signaling molecules. BRAF is a very important intermediary of the RAS-RAF-MEK-ERK pathway. BRAF mutations have been demonstrated in 6-8% of all malignancies. The most common BRAF mutation in melanoma is at the V600E/K site and is detected in approximately 50% of melanomas, and result in constitutive activation of the MAPK pathway.

TAFINLAR® (Dabrafenib) is a selective oral BRAF inhibitor and MEKINIST® (Trametinib) is a potent and selective inhibitor of MEK gene, which is downstream from RAF in the MAPK pathway. In patients with BRAF V600 mutation-positive unresectable or metastatic melanoma, a combination of TAFINLAR® and MEKINIST® resulted in a median Overall Survival (OS) of more than 2 years, with approximately 20% of the patients remaining progression free at 3 years. These encouraging results led to the study of this combination in patients with Stage III melanoma, with BRAF V600E or V600K mutations, after complete surgical resection.

COMBI-AD, an international, multi-center, randomized, double-blind, placebo-controlled, Phase III trial, in which 870 patients with completely resected Stage III melanoma, and with BRAF V600E or V600K mutations were enrolled. Patients were randomly assigned in a 1:1 to receive TAFINLAR® 150 mg orally twice daily in combination with MEKINIST® 2 mg orally once daily (N=438) or two matched placebos (N=432). Treatment was given for 12 months. Eligible patients had undergone completion lymphadenectomy, with no clinical or radiographic evidence of residual regional node disease. None of the patients had received previous systemic anticancer treatment or radiotherapy for melanoma. BRAF V600 mutation status was confirmed in primary tumor tissue or lymph node tissue by a central reference laboratory. The median age was 50 years. Both treatment groups were well balanced and 18% had Stage IIIA disease, 41% had Stage IIIB disease, and 40% had Stage IIIC disease. Of the enrolled patients, 91% had a BRAF V600E mutation, and 9% had a BRAF V600K mutation. The Primary end point was Relapse Free Survival (RFS) and Secondary end points included Overall Survival (OS), Distant Metastasis-Free Survival, Freedom from relapse, and Safety.

The authors had previously reported the results for RFS and Distant Metastasis-Free Survival at 5 years of follow up. Overall survival was not analyzed as the data was not mature. The minimum duration of follow up was 59 months. The RFS at 5 years was 52% with TAFINLAR® plus MEKINIST® and 36% with placebo (HR for relapse or death=0.51). The Distant Metastasis-Free Survival at 5 years was 65% with TAFINLAR® plus MEKINIST® and 54% with placebo (HR for distant metastasis or death=0.55). As has been reported in previous studies, majority of relapses occurred within the first 3 years after surgery.

The researchers herein reported the final results of the COMBI-AD trial after a long-term follow-up of more than 8 years. The RFS continued to favor TAFINLAR® plus MEKINIST® over placebo. The median RFS was 93.1 months with TAFINLAR® plus MEKINIST® and 16.6 months with placebo (HR for relapse or death= 0.52). The estimated RFS at 10 years was 48% with TAFINLAR® plus MEKINIST® and 32% with placebo. A relapse with distant metastasis occurred in 28% of patients in the combination-therapy group and in 37% of patients in the placebo group (HR for distant metastasis or death=0.56). The estimated Distant Metastasis-Free Survival at 10 years was 63% and 48%, respectively. The estimated Overall Survival at 8 years was 71% with TAFINLAR® plus MEKINIST® and 65% with placebo (HR for death=0.80; P=0.06). However, this benefit was not statistically significant. A consistent survival benefit was seen across several prespecified subgroups, including those with BRAF V600E mutated tumors (HR for death=0.75). There was no new safety signals noted.

It was concluded that after nearly 10 years of follow-up, 12 months of adjuvant therapy with a combination of TAFINLAR® plus MEKINIST® resulted in longer Relapse Free and Distant metastasis-free Survival, compared to placebo, among patients with resected Stage III melanoma, with 25% reduction in the risk of death among those with BRAF V600E mutations.

Final Results for Adjuvant Dabrafenib plus Trametinib in Stage III Melanoma. Long GV, Hauschild A, Santinami M, et al. N Engl J Med 2024;391:1709-1720.