Defining Patient Groups With Triple Negative Breast Cancer Who Derive Benefit From KEYTRUDA® plus Chemotherapy

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. Approximately 284,200 new cases of breast cancer will be diagnosed in 2021 and about 44,130 individuals will die of the disease, largely due to metastatic recurrence. Triple Negative Breast Cancer (TNBC) is a heterogeneous, molecularly diverse group of breast cancers and are ER (Estrogen Receptor), PR (Progesterone Receptor) and HER2 (Human Epidermal Growth Factor Receptor-2) negative. TNBC accounts for 15-20% of invasive breast cancers, with a higher incidence noted in young patients. It is usually aggressive, and tumors tend to be high grade and patients with TNBC are at a higher risk of both local and distant recurrence. Those with metastatic disease have one of the worst prognoses of all cancers with a median Overall Survival of 13 months. The majority of patients with TNBC who develop metastatic disease do so within the first 3 years after diagnosis, whereas those without recurrence during this period of time have survival rates similar to those with ER-positive breast cancers.

The lack of known recurrent oncogenic drivers in patients with metastatic TNBC, presents a major therapeutic challenge. It appears that there are subsets of patients with TNBC who may be inherently insensitive to cytotoxic chemotherapy. Three treatment approaches appear to be promising and they include immune therapies, PARP inhibition, and inhibition of PI3K pathway. Previously published studies have shown that presence of tumor-infiltrating lymphocytes was associated with clinical benefit, when treated with chemotherapy and immunotherapy, in patients with TNBC, and improved clinical benefit was observed in patients with immune-enriched molecular subtypes of metastatic TNBC.

KEYTRUDA® (Pembrolizumab) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor and blocks its interaction with ligands PD-L1 and PD-L2. It thereby reverses the PD-1 pathway-mediated inhibition of the immune response, and unleashes the tumor-specific effector T cells. The rationale for combining chemotherapy with immunotherapy is that cytotoxic chemotherapy releases tumor-specific antigens, and immune checkpoint inhibitors such as KEYTRUDA® when given along with chemotherapy can enhance endogenous anticancer immunity. Single agent KEYTRUDA® in metastatic TNBC demonstrated durable antitumor activity in several studies, with Objective Response Rates (ORRs) ranging from 10-21% and improved clinical responses in patients with higher PD-L1 expression. When given along with chemotherapy as a neoadjuvant treatment for patients with high-risk, early-stage TNBC, KEYTRUDA® combination achieved Pathological Complete Response rate of 65%, regardless of PD-L1 expression. Based on this data, KEYTRUDA® in combination with chemotherapy was studied, for first line treatment of advanced TNBC.

KEYNOTE-355 is a randomized, double-blind, Phase III study, which evaluated the benefit of KEYTRUDA® in combination with one of the three different chemotherapy regimens, nab-Paclitaxel, Paclitaxel, or the non-taxane containing Gemzar/Carboplatin, versus placebo plus one of the three chemotherapy regimens, in patients with previously untreated or locally recurrent inoperable metastatic TNBC. In this study, 847 patients were randomized 2:1 to receive either KEYTRUDA® 200 mg IV on day 1 of each 21-day cycle along with either nab-Paclitaxel 100 mg/m2 IV on days 1, 8 and 15 of each 28-day cycle, Paclitaxel 90 mg/m2 IV on days 1, 8 and 15 of each 28-day cycle, or Gemcitabine 1000 mg/m2 IV plus Carboplatin AUC 2, IV on days 1 and 8 of each 21-day cycle (N= 566) or placebo along with one of the three chemotherapy regimens (N= 281). This study was not designed to compare the efficacy of the different chemotherapy regimens. Treatment was continued until disease progression. Patients were stratified by chemotherapy, PD-L1 tumor expression (CPS-Combined Positive Score of 1 or higher versus CPS of less than 1), and prior treatment with the same class of neoadjuvant/adjuvant chemotherapy (Yes versus No). The baseline characteristics of treatment groups were well-balanced. The co-Primary end points of the trial were Progression Free Survival (PFS) and Overall Survival (OS) in patients with PD-L1-positive tumors, and in all patients. Secondary end points were Objective Response Rate (ORR), Duration of Response, Disease Control Rate, and Safety.

In the primary analysis of the KEYNOTE-355 trial, the Overall Survival results after a median follow up of 44.1 months in the subgroup of patients with PD-L1 CPS (Combined Positive Score) of 10 or more was significantly better with first line KEYTRUDA® plus chemotherapy versus placebo plus chemotherapy (23.0 months versus 16.1 months, respectively; HR=0.73; P=0.0093). This represented a 27% reduction in the risk of death with the KEYTRUDA® combination. KEYTRUDA® in combination with chemotherapy, also significantly improved PFS in patients with CPS (Combined Positive Score) of 10 or greater. The median PFS was 9.7 months for KEYTRUDA® plus chemotherapy, compared with 5.6 months for placebo plus chemotherapy (HR=0.65, P=0.0012). This represented a 35% reduction in the risk of disease progression. However, among patients with CPS of 1 or greater, the median PFS was not considered statistically significant, based on prespecified statistical criteria.

The researchers here in presented the results of a subgroup analysis, stratified by levels of PD-L1 expression, as assessed by CPS score. In the subgroups with CPS scores of less than 1 and 1-9, Overall Survival was similar for KEYTRUDA® plus chemotherapy and placebo plus chemotherapy. However, in subgroups with CPS 10-19 and CPS 20 or more, there was sustained separation of the Overall survival curves starting at approximately 10 months and the survival was improved by about 28%.

The authors noted that the general trend for PFS was consistent with that observed for Overall Survival, with improving PFS trend among those subgroups with PD-L1 enriched CPS of 10 or more. In the subgroup of patients with a CPS of 10-19 and CPS of 20 or more, the addition of KEYTRUDA® to chemotherapy resulted in a more sustained separation of PFS curves, beginning at approximately 4 months, compared with placebo plus chemotherapy. The Hazard Ratios for these two groups were 0.70 and 0.62, respectively. Toxicities of any grade were reported in 96% of the experimental group and 95% of the placebo plus chemotherapy group. The rate of Grades 3-5 treatment-related adverse events was 68.1% and 66.9%, respectively and the majority of treatment discontinuations in this study were for progressive disease.

The researchers based on this subgroup analyses concluded that a CPS of 10 or more is a reasonable cutoff to define the population of women with metastatic Triple Negative Breast Cancer, expected to derive treatment benefit from KEYTRUDA® plus chemotherapy, lending further support to KEYTRUDA® plus chemotherapy as a standard of care treatment regimen for this group of patients.

Final results of KEYNOTE-355: randomized, double-blind, phase 3 study of pembrolizumab + chemotherapy vs placebo + chemotherapy for previously untreated locally recurrent inoperable or metastatic triple-negative breast cancer. Cortés J, Cescon DW, Rugo HS, et al. Presented at: 2021 San Antonio Breast Cancer Symposium; December 7-10, 2021; San Antonio, TX. Abstract GS1-02.

Elevated White Cell Count and Risk of Thrombotic Events in Polycythemia Vera

SUMMARY: Polycythemia Vera (P. Vera) is a clonal myeloproliferative neoplasm characterized by isolated erythrocytosis in a majority of the patients, with the remaining demonstrating leukocytosis and/or thrombocytosis along with erythrocytosis. Patients usually present with this disorder in their sixth decade and are often asymptomatic, with the diagnosis made incidentally on routine laboratory evaluation. About 30% of the patients however, may initially present with a thrombotic episode, whereas a small percentage of patients may present with disease related symptoms such as pruritus and fatigue. The conventional risk factors for thrombotic events in MyeloProliferative Neoplasms (MPN) are age more than 60 years and prior thrombosis, and the presence of both these risk factors is associated with a 7-fold increased risk of thrombosis.

Overactivation of the JAK-STAT signal transduction pathway caused by V617F mutation has been implicated in majority of the patients with P. Vera. This pathway normally is responsible for passing information from outside the cell through the cell membrane to the DNA in the nucleus for gene transcription. Janus Kinase (JAK) family of tyrosine kinases are cytoplasmic proteins and include JAK1, JAK2, JAK3 and TYK2. JAK1 helps propagate the signaling of inflammatory cytokines whereas JAK2 is essential for growth and differentiation of hematopoietic stem cells. These tyrosine kinases mediate cell signaling by recruiting STAT’s (Signal Transducer and Activator of Transcription), with resulting modulation of gene expression. In patients with P. Vera, the aberrant myeloproliferation is the result of dysregulated JAK2-STAT signaling as well as excess production of inflammatory cytokines, associated with this abnormal signaling. JAK2 mutations such as JAK2 V617F are seen in approximately 95% of patients with P. Vera.Molecular-Mechanisms-of-MPNs

Studies have shown that JAK2 mutations that result in the overproduction of erythrocytes, leukocytes, and platelets in P. Vera also promote direct activation of leukocytes and platelets. Activated platelets and leukocytes bind to each other and activate endothelial cells, which may in turn contribute to the prothrombotic state. The prospective CYTO-PV trial published in 2011, established that maintaining hematocrit less than 45% through phlebotomies and/or cytoreductive drugs significantly decreased the risk of thrombotic events in P. Vera patients. Even though several retrospective analyses strongly suggest an association between leukocytosis and thrombosis, leukocytosis particularly at the time of the thrombotic event in P. Vera patients, no prospective trial has been conducted to assess the impact of WBC counts on thrombotic risk in P. Vera.

The REVEAL study is a large, real-world, multicenter, prospective, noninterventional, observational study, in which patients with P. Vera from US community practice and academic centers were enrolled , to evaluate the association between elevated blood counts and occurrence of thrombotic events in patients with P. Vera, using data from the REVEAL study.

This study analyzed the data of 2271 eligible patients for this analysis (78% high risk and 22% low risk). The median patient age was 66 years and 54% were male. The median disease duration was 4.1 years, 20% had a history of thrombotic events and majority of patients (53%) were receiving Hydroxyurea. Patient data was collected at diagnosis, at a 6-month period, and during follow up, 3 years from last patient enrollment, between July 2014 and August 2019 and the researchers analyzed the association between blood counts and thrombotic events. Out of 106 patients who had thrombotic events, 30 had arterial thrombotic events, most commonly, Transient Ischemic Attack and 76 had venous thrombotic events, most commonly, Deep Vein Thrombosis.

It was noted that hematocrit greater than 45% versus 45% or less (P=0.0028), WBC more than 11×109/L versus 11×109/L or less (P<0.0001), and Platelet counts more than 400×109/L versus 400×109/L or less (P=0.0170) were each associated with increased risk of thrombotic events. A WBC count of 11×109/L or more was associated with the highest thrombotic event risk compared with WBC count less than 7×109/L (P<0.0001). In all models analyzed, advanced age and history of thrombotic events, were associated with increased thrombotic event risk.

The authors concluded that in this analysis of the largest real-world cohort of P. Vera patients to date, hematocrit more than 45%, as well as WBC more than 11×109/L and Platelet counts more than 400×109/L, were each associated with increased risk of thrombotic events. The authors added that these data support the incorporation of blood count values into risk stratification and treatment strategies for patients with P. Vera in clinical practice, and to move beyond the conventional risk model.

A Real-World Evaluation of the Association between Elevated Blood Counts and Thrombotic Events in Polycythemia Vera (Analysis of Data from the REVEAL Study). Gerds AT, Mesa RA, Burke JM, et al. Presented at: 2021 ASH Annual Meeting and Exposition; December 11-14, 2021; Atlanta, GA. Abstract 239.

Acute Myeloid Leukemia: Who Is an Appropriate Candidate for ONUREG® (azacitidine) Tablets?

 

Written by: Thomas E Boyd, MD, Texas Oncology
Content Sponsored by: Bristol-Myers Squibb Company (BMS)

 

 

Dr. Boyd is a paid consultant for BMS and was compensated for his contribution in drafting this article.

Acute myeloid leukemia (AML) is a deadly disease with most new cases affecting patients aged 65–74 years old.1 The 5-year relative survival rate for AML is 29.5%1, highlighting a need for treatment approaches that improve survival.2 Patient- and disease-related characteristics, including medical fitness, age, cytogenetic and molecular testing, and risk of adverse events, often determine treatment options.3

After careful consideration of all factors, patients can be treated with either a higher-intensity chemotherapy option or a lower-intensity therapy option, and in some cases, additional cycles of consolidation therapy may follow the higher-intensity chemotherapy option.4 Helping patients achieve remission and keeping them there is a major goal of initial induction therapy. Continued treatment of AML in first remission may improve overall survival; however, relapse due to residual AML cells is still a major concern.2 In 764 patients with AML aged 60–85 years old who received induction therapy, ~50% relapsed within 1 year and ~80% relapsed within 5 years.5 A goal of continued treatment for AML is extending overall survival (OS) in patients who have achieved first remission.2 In some instances, extending OS can be achieved with a hematopoietic stem cell transplant; but not all patients are eligible or choose to go down this treatment route.3

ONUREG® is the first and only FDA-approved therapy indicated for continued treatment of adult patients with acute myeloid leukemia who achieved first complete remission (CR) or complete remission with incomplete blood count recovery (CRi) following intensive induction chemotherapy and are not able to complete intensive curative therapy.6 The efficacy and safety of ONUREG® was evaluated in the Phase 3 multicenter, randomized, double-blind placebo-controlled QUAZAR® AML-001 study.6 Eligible patients were ages 55 years or older, diagnosed with AML, were within 4 months of achieving first CR or CRi with intensive induction chemotherapy, and may have received consolidation therapy.6 Efficacy was established by OS, where ONUREG® demonstrated >2 years median OS for patients with AML in first remission as compared to placebo (24.7 months in the treatment arm vs 14.8 months in the placebo arm, hazard ratio (HR) 0.69, 95% confidence interval (CI): 0.55-0.86; P=0.0009).6 The most common adverse reactions (ARs, ≥ 10%) associated with ONUREG® treatment were nausea, vomiting, diarrhea, fatigue/asthenia, constipation, pneumonia, abdominal pain, arthralgia, decreased appetite, febrile neutropenia, dizziness, and pain in extremity.6 Serious ARs occurred in 15% of patients who received ONUREG®, and the most common Grade 3/4 ARs are shown in the table below.6

Who is an appropriate candidate for ONUREG®? The following hypothetical examples will review some of the characteristics to consider when deciding if a patient could be appropriate for ONUREG®.

Patient A is a 67-year-old retired accountant who is active and generally healthy. Their hypertension is well managed with medication, and they have no other comorbidities. Despite no family history of leukemia or hematologic abnormalities, Patient A has just been diagnosed with de novo AML not otherwise specified with intermediate-risk cytogenetics and no actionable mutations. Their hematologist prescribes intensive induction chemotherapy with the standard 7+3 regimen, and Patient A went into first remission.

Patient A is generally healthy with a well-managed comorbidity, which results in their treatment with intensive induction chemotherapy followed by first remission. Patient A is a candidate for transplant but declines one due to concerns over graft-versus-host disease. Since Patient A chose not to proceed to transplant, then ONUREG® may be an option for them.

Patient B is a 70-year retired nurse who lives alone, with family nearby. They were recently diagnosed with AML and received 7+3 chemotherapy followed by one round of consolidation. Patient B tolerated their treatment as well as could be expected and achieved first complete remission. While they are eligible for transplant, they declined and have been under observation by their doctor for the past few months. Patient B received and tolerated intensive induction chemotherapy, achieved first remission, and declined transplant, an intensive curative option. This makes them a potential candidate for continued treatment with ONUREG®.

Ultimately, the treating physician will make the final decision, but ONUREG® is indicated as a continued treatment of adult patients with AML who achieved first CR or CRi following intensive induction chemotherapy and are not able to complete intensive curative therapy.6 Understanding a patient’s disease and journey can help set them on the path where appropriate towards a continued treatment that has demonstrated an overall survival benefit in the QUAZAR® AML-001 study.

IMPORTANT SAFETY INFORMATION
CONTRAINDICATIONS
ONUREG® is contraindicated in patients with known severe hypersensitivity to azacitidine or its components.
WARNINGS AND PRECAUTIONS
Risks of Substitution with Other Azacitidine Products
Due to substantial differences in the pharmacokinetic parameters, the recommended dose and schedule for ONUREG® are different from those for the intravenous or subcutaneous azacitidine products. Treatment of patients using intravenous or subcutaneous azacitidine at the recommended dosage of ONUREG® may result in a fatal adverse reaction. Treatment with ONUREG® at the doses recommended for intravenous or subcutaneous azacitidine may not be effective. Do not substitute ONUREG® for intravenous or subcutaneous azacitidine.
Myelosuppression
New or worsening Grade 3 or 4 neutropenia and thrombocytopenia occurred in 49% and 22% of patients who received ONUREG®. Febrile neutropenia occurred in 12%. A dose reduction was required for 7% and 2% of patients due to neutropenia and thrombocytopenia. Less than 1% of patients discontinued ONUREG® due to either neutropenia or thrombocytopenia. Monitor complete blood counts and modify the dosage as recommended. Provide standard supportive care, including hematopoietic growth factors, if myelosuppression occurs.
Increased Early Mortality in Patients with Myelodysplastic Syndromes (MDS)
In AZA-MDS-003, 216 patients with red blood cell transfusion-dependent anemia and thrombocytopenia due to MDS were randomized to ONUREG® or placebo. 107 received a median of 5 cycles of ONUREG® 300 mg daily for 21 days of a 28-day cycle. Enrollment was discontinued early due to a higher incidence of early fatal and/or serious adverse reactions in the ONUREG® arm compared with placebo. The most frequent fatal adverse reaction was sepsis. Safety and effectiveness of ONUREG® for MDS have not been established. Treatment of MDS with ONUREG® is not recommended outside of controlled trials.
Embryo-Fetal Toxicity
ONUREG® can cause fetal harm when administered to a pregnant woman. Azacitidine caused fetal death and anomalies in pregnant rats via a single intraperitoneal dose less than the recommended human daily dose of oral azacitidine on a mg/m2 basis. Advise pregnant women of the potential risk to a fetus. Advise females of reproductive potential to use effective contraception during treatment with ONUREG® and for at least 6 months after the last dose. Advise males with female partners of reproductive potential to use effective contraception during treatment with ONUREG® and for at least 3 months after the last dose.
ADVERSE REACTIONS
Serious adverse reactions occurred in 15% of patients who received ONUREG®. Serious adverse reactions in ≥2% included pneumonia (8%) and febrile neutropenia (7%). One fatal adverse reaction (sepsis) occurred in a patient who received ONUREG®.
Most common (≥10%) adverse reactions with ONUREG® vs placebo were nausea (65%, 24%), vomiting (60%, 10%), diarrhea (50%, 21%), fatigue/asthenia (44%, 25%), constipation (39%, 24%), pneumonia (27%, 17%), abdominal pain (22%, 13%), arthralgia (14%, 10%), decreased appetite (13%, 6%), febrile neutropenia (12%, 8%), dizziness (11%, 9%), pain in extremity (11%, 5%).
LACTATION
There are no data regarding the presence of azacitidine in human milk or the effects on the breastfed child or milk production. Because of the potential for serious adverse reactions in the breastfed child, advise women not to breastfeed during treatment with ONUREG® and for 1 week after the last dose.

Please see full Prescribing Information for ONUREG®.

References
1. National Cancer Institute. SEER Cancer Statistics Factsheets: Acute Myeloid Leukemia. http://seer.cancer.gov/statfacts/html/amyl.html. Accessed April 21, 2021.
2. Medeiros BC, Chan SM, Daver NG, Jonas BA, Pollyea DA. Optimizing survival outcomes with post-remission therapy in acute myeloid leukemia. Am J Hematol. 2019;94:803-811.
3. Medeiros BC, Satram S. Real world treatment patterns and comparative effectiveness among elderly patients with acute myeloid leukemia in the United States. Ann Hematol Oncol. 2020;7(1):1283.
4. Burnett A, Wetzler M, Löwenberg B. Therapeutic advances in acute myeloid leukemia. J Clin Oncol. 2011;29(5):487-494.
5. Büchner T, Berdel WE, Haferlach C, et al. Age-related risk profile and chemotherapy dose response in acute myeloid leukemia: a study by the German Acute Myeloid Leukemia Cooperative Group. J Clin Oncol. 2009;27(1):61-69.
6. ONUREG®® [Prescribing Information]. Summit, NJ: Celgene Corporation; 2021.

© 2021 Celgene Corporation.
ONUREG® is a trademark of Celgene Corporation, a Bristol-Myers Squibb company.
QUAZAR® is a registered trademark Celgene Corporation, a Bristol-Myers Squibb company.
12/21 2011-US-2100198

Daprodustat: A New Oral Therapy for Anemia in Patients with Chronic Kidney Disease

SUMMARY: Anemia is a common complication of advanced renal failure. This is due to decreased Erythropoietin (EPO) production primarily due to the inability of the diseased kidney to adequately respond to hypoxia and/or anemia. Patients with Chronic Kidney Disease (CKD) are often given EPO replacement therapy which can be either recombinant human EPO (rhEPO) or reengineered preparations of recombinant EPO, and these agents are collectively referred to as Erythropoietin Stimulating Agents (ESA). These agents are administered by parenteral route and can reduce cardiovascular morbidity associated with anemia, blood transfusion requirements and improve quality of life. However, ESA given to normalize the hemoglobin level to 13-14.0 g/dl, as well as supraphysiologic dosing of ESA has been associated with increased risk of cardiovascular events, venous thromboembolism, CKD progression and overall mortality.

Systemic hypoxia increases plasma EPO levels, which in turn results in increased production of Red Blood Cells. New novel therapies include oral small molecule inhibitors that activate Hypoxia Inducible Factor (HIF) and stimulate endogenous EPO production.

HIF prolyl hydroxylase under conditions of normal oxygen concentrations breaks down the HIF. Daprodustat is an orally active HIF prolyl hydroxylase inhibitor that stimulates endogenous erythropoietin production by stabilizing the HIF-α subunit, allowing it to dimerize with the HIF-β subunit and to stimulate genes involved in protection against hypoxia, including the erythropoietin gene. In summary, Daprodustat increases hemoglobin levels as well as Total Iron Binding Capacity, and decreases the levels of ferritin and hepcidin. Daprodustat demonstrated a good safety profile and had efficacy over 24 weeks in Phase II trials involving patients with CKD.

In the current ASCEND-ND (Anemia Studies in Chronic Kidney Disease: Erythropoiesis via a Novel Prolyl Hydroxylase Inhibitor Daprodustat–Non-Dialysis) trial, the reserachers evaluated the efficacy and safety of the HIF prolyl hydroxylase inhibitor Daprodustat, as compared with the conventional ESA Darbepoetin alfa, in patients with CKD who were not undergoing dialysis. In this open-label, Phase III trial, 3872 patients were randomly assigned 1:1 to receive oral Daprodustat or subcutaneous Darbepoetin alfa. Eligible patients had stage 3-5 CKD and were not currently receiving dialysis or scheduled to start dialysis within 90 days, met the hemoglobin and ESA criteria, and had a serum ferritin level of more than 100 ng/ml and a transferrin saturation above 20%. Patients who had anemia that was unrelated to CKD, a recent cardiovascular event, or current or recent cancer were excluded.

The starting dose of Daprodustat was between 1 and 4 mg orally daily, according to the baseline hemoglobin level if the patient was not receiving an ESA, and according to the ESA dose if the patient was receiving an ESA, and dose adjustments ranged from 1 to 24 mg. The starting dose of subcutaneous Darbepoetin alfa was based on the patient’s weight and hemoglobin level at the time of randomization if the patient was not receiving an ESA or on the previous ESA dose if the patient was receiving an ESA. Dose increments were predefined, and the dose was increased by 25 to 33%. The study included a provision for the use of IV iron, PRBC transfusion, or both. The mean baseline hemoglobin levels were similar in the two treatment groups and was 9.9 plus or minus 0.9 g/dl. The researchers used a trial-specific algorithm for both treatment groups to achieve and maintain a hemoglobin level in the target range of 10-11 g/dl. Patient characteristics were well balanced in both treatment groups. Patients were evaluated at least every 4 weeks during the first year of the study and at least every 12 weeks thereafter. The Primary noninferiority outcomes were the mean change in the hemoglobin level from baseline to weeks 28 through 52, and the first occurrence of a Major Adverse Cardiovascular Event (MACE- a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke). These and other cardiovascular events were adjudicated by a blinded independent committee.

Daprodustat was noted to be noninferior and as effective as Darbepoetin alfa in increasing and maintaining hemoglobin levels in patients with CKD and anemia who were not receiving dialysis, and this benefit on hemoglobin levels was consistent across prespecified subgroups. Daprodustat was also noninferior to Darbepoetin alfa with respect to cardiovascular safety in the primary analysis. During a median follow up of 1.9 years, a first MACE occurred in 19.5% of patients in the Daprodustat group and 19.2% of patients in the Darbepoetin alfa group, and this met the prespecified noninferiority margin. There was no difference in the rates of thromboembolic events and hospitalization for heart failure among the treatment groups.

It was noted that patients in the Daprodustat group had more esophageal or gastric erosions (3.6%), compared to 2.1% in the Darbepoetin alfa group. Because of the activation of the HIF pathway by HIF prolyl hydroxylase inhibitor, cancer incidence and progression is a concern and the researchers observed a higher incidence of cancer-related death or tumor progression or recurrence in the Daprodustat group (3.7%) compared to 2.5% in the Darbepoietin alfa group (Relative Risk=1.47)

It was concluded from this study that among patients with CKD and anemia who were not undergoing dialysis, Daprodustat was noninferior to Darbepoetin alfa with respect to the change in the hemoglobin level from baseline and with respect to cardiovascular outcomes. However, the safety of HIF prolyl hydroxylase inhibitors in cancer patients will require longer follow up.

Daprodustat for the Treatment of Anemia in Patients Not Undergoing Dialysis. Singh AK, Carroll K, McMurray JV, et al. for the ASCEND-ND Study Group. N Engl J Med 2021; 385:2313-2324.

Long Term Survival Benefit with Maintenance ONUREG® in AML Patients

SUMMARY: The American Cancer Society has estimated that in 2021, 20,240 new cases of Acute Myeloid Leukemia (AML) were diagnosed in the United States and 11,400 patients died 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 (OS) 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.

Cytotoxic chemotherapy for AML often consists of induction therapy to achieve remission, followed by consolidation therapy. However, standard induction chemotherapy achieves Complete Remission in only 40-60% of AML patients older than 60 years of age, and majority of these patients will eventually relapse. This had been attributed to clonal evolution and epigenetic reprogramming, leading to aberrant DNA methylation, and persistence of leukemia-initiating cells.

Longer duration of first remission is associated with better survival outcomes. Postremission maintenance therapies to prevent early AML relapse has been an area of active research with little progress made until now. Patients with AML who are under age 55 with high-risk cytogenetics, in first clinical remission,are considered for allogeneic Hematopoietic Stem Cell Transplantation (HSCT), as this has shown to offer survival advantage over conventional chemotherapy. This therapeutic option however is not feasible for many elderly patients.

Oral Azacitidine (ONUREG®) is a hypomethylating agent that has a distinct pharmacokinetic as well as pharmacodynamic profile from the parenteral Azacitidine preparation, and can be administered in extended dosing schedules (for 14-21 days per 28-day treatment cycle) to sustain therapeutic activity.

ONUREG® is the first and only FDA-approved therapy indicated for continued treatment of adult patients with AML who achieved first Complete Remission (CR) or Complete Remission with incomplete blood count recovery (CRi) following intensive induction chemotherapy, and are not able to complete intensive curative therapy.

This FDA approval was based on an International, double-blind, placebo-controlled, Phase III QUAZAR AML-001 trial, in which ONUREG® was evaluated as maintenance therapy in patients with AML, who were in first remission after intensive chemotherapy. Eligible patients were 55 years of age or older, were in complete remission with or without complete blood count recovery, and were not candidates for Hematopoietic Stem Cell Transplantation. Patients (N=472) were randomly assigned to receive ONUREG® 300 mg orally (N=238) or placebo (N=234), once daily for 14 days of a 28-day cycle. The median age was 68 years. The Primary end point was Overall Survival (OS). Secondary end points included Relapse Free Survival (RFS) and Health-Related Quality of Life.

At the time of the primary analysis in 2019, with a median follow up of 41.2 months, maintenance treatment with ONUREG® significantly prolonged median OS, when compared to placebo (24.7 months versus 14.8 months; P<0.001). The median RFS was also significantly longer with ONUREG® than with placebo (10.2 months versus 4.8 months; P<0.001). These survival benefits were demonstrated in most treatment subgroups. Further, with a median follow up of 51.7 months, the median OS remained unchanged, and the median OS with oral ONUREG® was 24.7 months versus 14.8 months with placebo (HR=0.69; P=0.0008). The 3-year OS rates in the experimental and control arms were 37.4% and 27.9%, respectively and at 5 years were 26.2% and 19.2%, respectively. Overall Quality of life was preserved while on treatment with ONUREG®. The most common adverse reactions associated with ONUREG® treatment were nausea, vomiting, diarrhea, abdominal pain, constipation, fatigue/asthenia, febrile neutropenia and pneumonia.

The authors concluded that maintenance treatment with ONUREG® was associated with significantly longer Overall and Relapse Free Survival when compared to placebo, among elderly patients with AML, who were in remission after chemotherapy. This survival benefit was maintained with one additional year of follow up. The researchers added that these updated data suggests that maintenance therapy with ONUREG® provides a sustained, long term Overall Survival benefit in elderly patients with AML in first remission.

Long-Term Overall Survival (OS) with Oral Azacitidine (Oral-AZA) in Patients with Acute Myeloid Leukemia (AML) in First Remission after Intensive Chemotherapy (IC): Updated Results from the Phase 3 QUAZAR AML-001 Trial. Wei AH, Döhner H, Sayar H, et al. Blood. 2021;138(suppl 1):871. doi:10.1182/blood-2021-147501.

Postmenopausal Women with Node Positive Breast Cancer May Not Benefit From Chemotherapy

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. Approximately 284,200 new cases of breast cancer will be diagnosed in 2021 and about 44,130 individuals will die of the disease, largely due to metastatic recurrence. Approximately 25% of patients with Hormone Receptor (HR)-positive, HER2-negative early breast cancer have metastatic lymph node involvement and two third of these patients are postmenopausal. Majority of these patients currently receive adjuvant chemotherapy.

The Oncotype DX breast cancer assay, is a multigene genomic test that analyzes the activity of a group of 21 genes and is able to predict the risk of breast cancer recurrence and likelihood of benefit from systemic chemotherapy, following surgery, in women with early stage breast cancer. Chemotherapy recommendations for early stage, HR-positive, HER-negative, early stage breast cancer patients, are often made based on tumor size, grade, ImmunoHistoChemical (IHC) markers such as Ki-67, nodal status and Oncotype DX Recurrence Score (RS) assay.

In the ground-breaking TAILORx (Trial Assigning Individualized Options for Treatment) study which enrolled 10,273 patients with HR-positive, HER2-negative, axillary node-negative breast cancer, patients were divided into three groups based on their Recurrence Score. Patient with Intermediate Recurrence Score of 11-25 were randomly assigned to receive endocrine therapy alone or endocrine therapy and adjuvant chemotherapy. There was no benefit noted from adding chemotherapy to endocrine therapy, for women older than 50 years in this Intermediate RS group, suggesting that a significant percentage of women with node-negative breast cancer do not achieve substantial benefit from chemotherapy. For women 50 years old or younger who received chemotherapy and had a Recurrence Score of at least 16, there was a lower rate of distant recurrence, and the absolute benefit increased with increasing recurrence score. Further, the risk of recurrence and benefit of chemotherapy was further influenced by the tumor size and grade.

Whether the results of TAILORx can be extrapolated to women with node-positive breast cancer has remained unclear. It is estimated that approximately 85% of women with node-positive disease have Recurrence Score results of 0-25. The RxPONDER (A Clinical Trial RX for Positive Node, Endocrine Responsive Breast Cancer) trial was designed to determine the benefit of chemotherapy, in patients with HR-positive, HER2-negative breast cancer and 1-3 positive axillary lymph nodes (nodal stage N1), who had a Recurrence Score of 0-25. This trial did not include pre and postmenopausal women with Recurrence Score results 26-100, based on previously published studies suggesting that this patient group benefited from chemotherapy.

SWOG S1007 (RxPONDER) is an multicenter, international, prospective, randomized, Phase III trial, in which patients with HR-positive, HER2-negative breast cancer with 1-3 positive axillary lymph nodes were included, to determine which patients would benefit from chemotherapy and which patients could safely avoid it. In this study, a total of 5083 HR-positive, HER2-negative breast cancer patients with 1-3 positive lymph nodes and Oncotype DX Recurrence Score of less than 25 were randomly assigned 1:1 to receive chemotherapy plus endocrine therapy (N=2547) or endocrine therapy alone (N=2536). The median patient age was 57.5 years and approximately two-thirds of patients were postmenopausal and one-third were premenopausal and had no contraindications to taxane and/or anthracycline based chemotherapy. Patients were stratified by Recurrence Score (0-13 versus 14-25), menopausal status, and axillary nodal dissection versus sentinel node biopsy. The Primary endpoint was Invasive Disease Free Survival (IDFS), defined as local, regional, or distant recurrence, any second invasive cancer, or death from any cause, and whether the effect depended on the Recurrence Score. Secondary endpoints included distant Relapse Free Survival (RFS) and Overall Survival (OS).

At a median follow up of 6.1 years, the chemotherapy benefit with respect to increasing invasive DFS differed according to menopausal status. Among postmenopausal women, in this updated analysis with longer follow up, the invasive DFS at 5 years was 91.9% in the endocrine therapy alone group, and was 91.3% in those treated with chemotherapy plus endocrine therapy (HR=1.02; P=0.89). Postmenopausal women with recurrence scores of 0 to 25 continued to NOT benefit from adjuvant chemotherapy.

Among premenopausal women however, the invasive DFS at 5 years was 89% in the endocrine therapy alone group and 93.9% % in those treated with chemotherapy plus endocrine therapy (HR=0.64; P=0.004). There was a 5-year absolute benefit of 4.9% for invasive DFS with chemotherapy among premenopausal women. There was a similar increase noted in the distant Relapse Free Survival (HR=0.58; P=0.009). The relative chemotherapy benefit did not increase as the Recurrence Score increased.

It was concluded from this practice-changing study that postmenopausal women with HR-positive, HER2-negative breast cancer with 1-3 positive nodes and Oncotype DX Recurrence Score of 25 or less, can safely avoid receiving adjuvant chemotherapy, whereas premenopausal patients with 1-3 positive nodes and a Recurrence Score of 25 or less benefited from chemotherapy plus endocrine therapy and had a longer invasive Disease Free Survival and distant Relapse Free Survival, than those who received endocrine therapy alone.

21-Gene Assay to Inform Chemotherapy Benefit in Node-Positive Breast Cancer. Kalinsky K, Barlow WE, Gralow JR, et al. N Engl J Med 2021;385:2336-2347

POLIVY® in Previously Untreated Diffuse Large B-Cell Lymphoma

SUMMARY: The American Cancer Society estimates that in 2021, about 81,560 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,720 individuals will die of this disease. Diffuse Large B-Cell Lymphoma (DLBCL) is the most common of the aggressive Non-Hodgkin lymphoma’s in the United States, and the incidence has steadily increased 3-4% each year. More than half of patients are 65 or older at the time of diagnosis and the incidence is likely to increase with aging of the American population. The etiology of Diffuse Large B-Cell Lymphoma is unknown. Contributing risk factors include immunosuppression (AIDS, transplantation setting, autoimmune diseases), UltraViolet radiation, pesticides, hair dyes, and diet.

DLBCL is a neoplasm of large B cells and the most common chromosome abnormality involves alterations of the BCL-6 gene at the 3q27 locus, which is critical for germinal center formation. Two major molecular subtypes of DLBCL arising from different genetic mechanisms have been identified, using gene expression profiling: Germinal Center B-cell-like (GCB) and Activated B-Cell-like (ABC). Patients in the GCB subgroup have a higher five year survival rate, independent of clinical IPI (International Prognostic Index) risk score, whereas patients in the ABC subgroup have a significantly worse outcome. Regardless, R-CHOP regimen (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone), given every 21 days, for 6 cycles, delivered with curative intent, is the current standard of care for patients of all ages, with newly diagnosed DLBCL, regardless of molecular subtype. Approximately 30-40% of patients experience disease progression or relapse, during the first 2 years and attempts to improve on R-CHOP regimen have not been successful. Maintenance treatment strategy following R-CHOP, to better control the disease, delay disease progression and improve long term survival, have included Autologous Stem Cell Transplantation, maintenance treatment with agents such as oral protein kinase inhibitor Enzastaurin and Everolimus. Outcomes for transplant-ineligible patients with Relapsed/Refractory DLBCL patients remain poor.

CD79b is a B-cell specific surface protein, which is a component of the B-cell receptor and is ubiquitously expressed on the surface of malignant B cells. POLIVY® (Polatuzumab vedotin) is a CD79b-directed Antibody-Drug Conjugate (ADC) with activity against dividing B cells. It consists of three components: 1) the humanized ImmunoGlobulin G1 (IgG1) monoclonal antibody specific for human CD79b; 2) the small molecule anti-mitotic agent MMAE (monomethyl auristatin E) and 3) a protease-cleavable linker that covalently attaches MMAE to the Polatuzumab antibody. Upon binding to CD79b, POLIVY® is internalized, and the linker is cleaved by lysosomal proteases thus enabling intracellular delivery of MMAE. MMAE then binds to microtubules and kills dividing cells by inhibiting cell division and inducing apoptosis. POLIVY® demonstrated efficacy in patients with Relapsed or Refractory DLBCL, resulting in significantly longer Overall Survival when combined with Bendamustine and Rituximab, compared to Bendamustine and Rituximab alone. Based on these finding, the FDA granted accelerated approval to POLIVY® in June 2019.

In a Phase Ib-II study POLIVY® in combination with Rituximab, Cyclophosphamide, Doxorubicin, and Prednisone (pola-R-CHP) resulted in a 89% Overall Response rate and 77% Complete Responses when given as first line therapy, in patients with DLBCL. In this study, Vincristine was excluded from the regimen owing to the risk of overlapping neurotoxicities with POLIVY®. The present POLARIX trial was conducted to evaluate the efficacy and safety of pola-R-CHP as compared with R-CHOP, in patients with previously untreated DLBCL.

The POLARIX is a randomized, double-blind, placebo-controlled, International Phase III trial in which a total of 879 treatment naïve, CD20-positive, intermediate or high-risk DLBCL patients were randomly assigned in a 1:1 ratio to receive 6 cycles of either pola-R-CHP (N=440) or R-CHOP (N=439). Patients on Day 1 of each 21 day cycle, received POLIVY® 1.8 mg/kg IV and a placebo matching Vincristine IV (pola-R-CHP group) or a placebo matching POLIVY® and intravenous Vincristine at a dose of 1.4 mg/m2 (maximum of 2 mg) (R-CHOP group), along with Rituximab 375 mg/m2 IV, Cyclophosphamide 750 mg/m2 IV and Doxorubicin 50 mg/m2 IV. All the patients also received Prednisone 100 mg orally once daily on Days 1-5 of each of the first six cycles. During cycles 7 and 8, patients in both treatment groups received Rituximab monotherapy at 375 mg/m2 IV. The median patient age was 65 years and stratification was based on IPI score and presence or absence of bulky disease, Subtypes of DLBCL were centrally evaluated and were balanced between the two treatment groups. Patients were eligible regardless of the Cell of Origin or the presence of rearrangements in MYC, BCL2, BCL6, or a combination of these. Patients with known CNS involvement were excluded but CNS prophylaxis with intrathecal chemotherapy was permitted, in accordance with institutional practice guidelines. The use of Granulocyte Colony-Stimulating Factor (G-CSF) was required during the first six cycles of treatment for primary prophylaxis against neutropenia and consolidative radiotherapy to initial sites of bulky disease or extranodal sites was allowed at the discretion of the investigator. The Primary end point was Progression Free Survival (PFS). Secondary end points included Overall Survival (OS) and Safety.

At a median follow up of 28.2 months, the PFS was significantly higher in the pola-R-CHP group compared to the R-CHOP group. The PFS at 2 years was 76.7% in the pola-R-CHP group versus 70.2% in the R-CHOP group (stratified HR=0.73; P=0.02). Treatment with pola-R-CHP resulted in a risk of disease progression, relapse, or death that was 27% lower, compared to R-CHOP. Patient subgroups that did not show a clear benefit with pola-R-CHP included patients 60 years of age or younger, patients with the Germinal Center B-cell-like subtype of DLBCL, patients who had bulky disease, and patients who had lower IPI scores. Overall Survival at 2 years did not differ significantly between the treatment groups and the researchers attributed the lack of a significant difference between the two groups in Overall Survival, to the availability of new, effective treatments for relapsed or refractory DLBCL, as well as short duration of follow up at the time of this reporting. The safety profile was similar in the two treatment groups.

The authors concluded that among patients with previously untreated intermediate-risk or high-risk DLBCL, the risk of disease progression, relapse, or death was lower among those who received pola-R-CHP than among those who received R-CHOP.

Polatuzumab Vedotin in Previously Untreated Diffuse Large B-Cell Lymphoma. Tilly H, Morschhauser F, Sehn LH, et al. December 14, 2021. DOI: 10.1056/NEJMoa2115304

Risk of Cardiovascular Diseases among Older Breast Cancer Survivors

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. Approximately 284,200 new cases of breast cancer will be diagnosed in 2021 and about 44,130 individuals will die of the disease, largely due to metastatic recurrence.

Significant progress in breast cancer screening techniques, as well as new and novel therapies, have resulted in early cancer detection and improvement in the breast cancer 5-year survival rate in the US from 75% in the 1970s to 91% in the 2010s. Cardiovascular Disease (CVD) is the most frequent cause of noncancer-related death, and cardiotoxicities associated with cancer treatments may increase cardiovascular risk in this population of breast cancer survivors. However, few studies have in detail quantified the risks of the different clinically important cardiovascular outcomes. The authors therefore assessed the prevalence of the different clinically specific cardiovascular outcomes at breast cancer diagnosis, and their incidence after diagnosis, among survivors 65 years or older in the US, and compared this with similar women without cancer.

The researchers performed a matched cohort study using prospectively collected data from the SEER-Medicare linked claims-based database and identified all women older than 65 years of age with an incident Stage I-III breast cancer diagnosis in 2004 through 2013. Each patient with breast cancer was matched at diagnosis with 5 cancer-free female counterparts. Baseline prevalence of specific cardiovascular outcomes was measured, and the risk for individual cardiovascular outcomes during follow up was calculated, taking into consideration time since diagnosis, race/ethnicity, prior Cardiovascular Disease (CVD), and age. This study included a total of 91,473 women with breast cancer and 454,197 without breast cancer.

It was noted that women with breast cancer had lower baseline prevalence of all CVDs. Breast cancer survivors had substantially increased risks of Deep Vein Thrombosis and pericarditis, compared with cancer-free female counterparts. There was also evidence of smaller increased risks of sudden cardiac arrest, arrhythmia, heart failure, and valvular heart disease. The increased risks of arrhythmia, heart failure, pericarditis, and Deep Vein Thrombosis were most pronounced in the first year and persisted for more than 5 years after cancer diagnosis. There was evidence of a decreased risk of incident angina, myocardial infarction, revascularization, peripheral vascular disease, and stroke in breast cancer survivors, although this was not constant over time.

The CVD risk during follow up was consistently higher in African American women diagnosed with breast cancer compared with Caucasian women, regardless of whether there was an overall increased or decreased risk of outcomes during the entire follow up period, and this is consistent with racial differences in overall CVD risk in the US.

Finally, there was consistently a greater risk of all cardiovascular outcomes in those diagnosed with Stage III, Grade 3, and ER/PR-negative breast cancer, which may be a reflection of the more aggressive cancer treatment regimens used in these subtypes.

The authors concluded that there is evidence of increased risk of several cardiovascular diseases in elderly women diagnosed with breast cancer in the US, compared with similar women without cancer, with this risk persisting for several years after diagnosis. They added that these results highlight the importance of periodic cardiovascular evaluation throughout the long term follow up of women diagnosed with breast cancer.

Risk of Cardiovascular Diseases Among Older Breast Cancer Survivors in the United States: A Matched Cohort Study. Matthews AA, Hinton SP, Stanway S, et al. J Natl Compr Canc Netw 2021;19:275-284.

KRAS Variant Status and Outcomes with Immune Checkpoint Inhibitor-Based Therapy in Advanced Non Small Cell Lung Cancer

SUMMARY: The American Cancer Society estimates that for 2021, about 235,760 new cases of lung cancer will be diagnosed and 131,880 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 histologic subtype of lung cancer.

Patients with advanced NSCLC without a driver mutation and with Programmed cell Death Ligand 1 (PD-L1) expression of 50% or greater, are often treated first line with Immune Checkpoint Inhibition (ICI) monotherapy or ICI in combination with chemotherapy. The choice between these two treatment regimens is usually based on tumor burden and patient comorbidities, as there are presently no biomarkers available to predict the risk and benefit of these treatment interventions. The KEYNOTE-042 study demonstrated that single agent Pembrolizumab given as first line therapy demonstrated Overall Survival (OS) benefit over chemotherapy, in patients with previously untreated advanced NSCLC, with PD-L1 expression of 1% or greater. In an exploratory analysis, this benefit was seen regardless of KRAS status, but was more pronounced in patients with KRAS variants than those without KRAS variants.

The KRAS (kirsten rat sarcoma viral oncogene homologue) proto-oncogene encodes a protein that is a member of the small GTPase super family. The KRAS gene provides instructions for making the KRAS protein, which is a part of a signaling pathway known as the RAS/MAPK pathway. When mutated, KRAS oncogene has the potential to change normal cells cancerous. KRAS is the most frequently mutated oncogene in human cancers and are often associated with resistance to targeted therapies and poor outcomes. The KRAS-G12C mutation occurs in approximately 12-15% of NSCLC and in 3-5% of Colorectal cancers and other solid cancers. KRAS G12C is one of the most prevalent driver mutations in NSCLC and accounts for a greater number of patients than those with ALK, ROS1, RET, and TRK 1/2/3 mutations combined. KRAS G12C cancers are genomically more heterogeneous and occur more frequently in current or former smokers, and are likely to be more complex genomically than EGFR mutant or ALK rearranged cancers.

The authors conducted this study to evaluate the association of KRAS status with outcomes following ICI monotherapy versus chemoimmunotherapy in patients with PD-L1 of 50% or greater. The researchers used the Flatiron Health database, comprising 280 cancer clinics across the US and analyzed 1127 patients with advanced non-squamous NSCLC with PD-L1 expression of 50% or greater, known KRAS variant status, and no alteration in EGFR, ALK, or ROS1, who were treated with first line ICI monotherapy or chemoimmunotherapy between January 2016 and May 2020. Of the patients analyzed, 50.8% had KRAS variant status and 49.2% had KRAS wild type status. Patients with KRAS variant status were more likely to be female (58.7% versus 47.1%; P =0.002) and had smoking history (96.4% versus 87.7%; P < .001). Other patient demographics and patient characteristics, including age, race, ethnicity, Performance Status, and stage at diagnosis, were well balanced among the groups analyzed. Patient groups were stratified by treatment type and KRAS status (variant or wild type), and Overall Survival (OS) was compared between the treatment groups. Adjusted Hazard ratios for death associated with KRAS status and treatment regimen was estimated, using Cox proportional hazards models.

It was noted that among patients treated with ICI monotherapy, KRAS variant status was associated with superior median survival compared with KRAS wild type (21.1 months versus 13.6 months; HR=0.77; P=0.03), and this was statistically significant. However, among patients treated with chemoimmunotherapy, there was no significant median survival difference between patients with KRAS variant and KRAS wild type status (20.0 months versus 19.3 months; HR=0.99; P=0.93).

Among patients with KRAS variant status, the median OS did not differ between those treated with ICI monotherapy and chemoimmunotherapy (21.1 months versus 20.0 months; P =0.78), whereas among patients with KRAS wild type status, those treated with ICI monotherapy had numerically worse median survival than those treated with chemoimmunotherapy, although this difference was not statistically significant (13.6 months versus 19.3 months; HR=1.19; P =0.06).

In conclusion, this data suggests that chemoimmunotherapy might be favored over ICI monotherapy for patients with KRAS wild type tumors associated with high PD-L1 expression. The authors caution that in this analysis KRAS variant subtype and co-mutation status including TP53 and STK11 was unknown, and further investigation is needed to selection appropriate therapies for patients with PD-L1 High NSCLC.

Association Between KRAS Variant Status and Outcomes With First-line Immune Checkpoint Inhibitor–Based Therapy in Patients With Advanced Non–Small-Cell Lung Cancer. Sun L, Hsu M, Cohen RB, et al. JAMA Oncol. 2021;7:937-939.

Duration of Adjuvant Aromatase Inhibitor Therapy in Postmenopausal Breast Cancer

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. Approximately 284,200 new cases of breast cancer will be diagnosed in 2021 and about 44,130 individuals will die of the disease, largely due to metastatic recurrence.

Luminal breast cancer is the most prevalent molecular subtype in postmenopausal females, accounting for over 70%. Despite substantial improvements in adjuvant therapies, the risk of disease recurrence continues indefinitely, with more than half the recurrences occurring after the first 5 years following diagnosis. Following initial adjuvant endocrine therapy with Tamoxifen for 5 years, the addition of extended adjuvant therapy has resulted in 40% longer Disease Free Survival (DFS), when compared to placebo or no extended therapy. However the benefit of extending adjuvant Aromatase Inhibitor therapy for 5 years beyond the initial 5-year duration regimen is less well established. Further, the most effective duration of such extended adjuvant endocrine therapy remains unclear. Added to this dilemma are the side effects associated with Aromatase Inhibitor therapy including hot flushes, arthralgia, and bone pain, as well as treatment-induced osteoporosis, which can have a significant impact on patient’s quality of life. Researchers in the Secondary Adjuvant Long-Term Study with Arimidex [Anastrozole] (SALSA) prospectively investigated whether an additional 2 years or 5 years of Anastrozole therapy would result in better outcomes, following the initial 5 years of endocrine therapy, in postmenopausal women with Hormone Receptor-positive breast cancer.

The authors conducted a prospective, multicenter, randomized, Phase III trial, which included 3,470 eligible postmenopausal women with Stages I, II or III early stage breast cancer with no evidence of recurrence. Enrolled patients had invasive Hormone Receptor-positive breast cancer, and had received 5 years (plus or minus 12 months) of adjuvant endocrine therapy with Tamoxifen, Aromatase Inhibitors, or both sequentially, up until 12 months before randomization. Patients were randomly assigned 1:1 to receive Anastrozole 1 mg, orally daily, for either 2 additional years for a total of 7 years (N=1732) or 5 additional years for a total of 10 years (N=1738). The two treatment groups were well balanced. The median age at the time of randomization was 64 years, 72% of patients had tumors that were smaller than 2 cm, 66% had node-negative disease, and 19% had high-grade tumors. Stratification criteria included pathological tumor stage, pathological node stage, primary adjuvant endocrine therapy and adjuvant chemotherapy.

The primary analysis included all the patients who were still participating in the study (N=3208), including 1,603 in the 2-year group versus 1,605 in the 5-year group. In the primary analysis population of 3208 patients, 51% had received Tamoxifen alone for the initial 5 years, 7.3% had received an Aromatase Inhibitor alone, and 41.7% had received an Aromatase Inhibitor in combination with Tamoxifen. The Primary end point was Disease Free Survival (DFS). Secondary end points were Overall Survival (OS), contralateral breast cancer, second primary cancer, and clinical bone fracture. The median follow-up after randomization was 118 months.

The researchers observed no difference in DFS with 2 versus 5 additional years of adjuvant endocrine therapy with Anastrozole. The DFS 10 years since randomization was 73.6% in the 2-year group versus 73.9% in the 5-year group (HR=0.99; P=0.90). Contralateral breast cancer occurred in 2.2% versus 2.1% of patients (HR= 1.15), and local recurrence occurred in 3% versus 2.4% in the 2 year and 5 year groups, respectively. There was no difference noted for Overall Survival at 8 years between the two treatment groups (87.5% in the 2-year group and 87.3% in the 5-year group, HR for death from any cause=1.02). The risk of clinical bone fracture however was higher in the 5-year group than in the 2-year group (HR=1.35).

It was concluded from this study that in postmenopausal women with Hormone Receptor positive breast cancer who had received 5 years of adjuvant endocrine therapy, extending endocrine therapy with an Aromatase Inhibitor by an additional 5 years provided no benefit over a 2-year extension, but was associated with a greater risk of bone fracture.

Duration of Adjuvant Aromatase-Inhibitor Therapy in Postmenopausal Breast Cancer. Gnant M, Fitzal F, Rinnerthaler G, et al. N Engl J Med 2021; 385:395-405.