Immediate ADT Confers Survival Benefit in Prostate Cancer Patients with “Biochemical Recurrence”

SUMMARY: Prostate cancer is the most common cancer in American men excluding skin cancer and 1 in 7 men will be diagnosed with prostate cancer during their lifetime. It is estimated that in the United States, about 220,800 new cases of prostate cancer will be diagnosed in 2015 and over 27,000 men will die of the disease. The major source of PSA (Prostate Specific Antigen) is the prostate gland and the PSA levels are therefore undetectable within 6 weeks after Radical Prostatectomy. Similarly, following Radiation Therapy, there is a gradual decline in PSA before reaching a post treatment nadir. A detectable PSA level after Radical Prostatectomy, or a rising PSA level following Radiation Therapy, is considered PSA failure or biochemical recurrence. The American Urological Association suggested that a PSA of 0.2 ng/mL or higher after Radical Prostatectomy, defines PSA failure or relapse. A PSA rise of 2 ng/ml or more above post Radiation Therapy nadir is considered PSA failure or relapse. Approximately 35% of the patients with prostate cancer will experience PSA only relapse within 10 years of their primary treatment and a third of these patients will develop documented metastatic disease within 8 years following PSA only relapse. The development and progression of prostate cancer is driven by androgens. Androgen Deprivation Therapy (ADT) has therefore been the cornerstone of treatment of advanced prostate cancer and is the first treatment intervention for hormone sensitive prostate cancer. The appropriate time (immediate versus delayed) to start Androgen Deprivation Therapy (ADT) in patients with prostate cancer with rising Prostate-Specific Antigen (PSA), as the only sign of relapse, has remained unclear. This has been partly due to lack of patient accruals and patient reluctance to be randomized, in these clinical trials.

The authors conducted this randomized, prospective, phase III trial, to determine if immediate intervention with Androgen Deprivation Therapy (ADT) would improve Overall Survival (OS), compared with delayed ADT, in prostate cancer patients with PSA relapse, following definitive therapy, or in asymptomatic men not suitable for definitive therapy at the time of diagnosis. This analysis combined prostate cancer patients with PSA relapse enrolled in two separate studies. Two hundred and ninety three (N=293) eligible patients were randomly assigned 1:1 to immediate Androgen Deprivation Therapy (N= 142) or delayed ADT (N=151). The primary endpoint was unadjusted Overall Survival. Secondary endpoints included cancer-specific survival and time to clinical progression. The median follow up was 5 years. There was a statistically significant improvement in the Overall Survival, with a 45% reduction in the risk for death, for those receiving immediate ADT compared with the delayed treatment group (HR=0.55; P=0.05). Further, with immediate ADT, there was a statistically significant delay in the time to first local progression (HR= 0.51; P=0.001) as well as time to first metastatic disease (HR=0.54; P=0.018). The authors concluded that immediate Androgen Deprivation Therapy significantly improved Overall Survival and time to clinical progression for prostate cancer patients with PSA relapse, after definitive therapy. This benefit however must be weighed against the risks associated with long term Androgen Deprivation Therapy. TROG 03.06 and VCOG PR 01-03: The “Timing Of Androgen Deprivation therapy in prostate cancer patients with a rising PSA (TOAD)” collaborative randomised phase III trial. Duchesne GM, Bassett J, D’Este C, et al. J Clin Oncol 33, 2015 (suppl; abstr 5007)

Late Breaking Abstract – ASCO 2015 IMBRUVICA® in Combination with BR Regimen Shows Significant Benefit in Relapsed CLL patients

SUMMARY: The American Cancer Society estimates that approximately 14,620 new cases of Chronic Lymphocytic Leukemia (CLL) will be diagnosed in 2015 and approximately 4650 patients will die from the disease. CLL is a disease of the elderly and the average age at the time of diagnosis is 72 years. There are two main types of lymphocytes, B and T lymphocytes/cells. B-cell CLL is the most common type of leukemia in adults. Normal B-cell activation and proliferation is dependent on B-cell receptor (BCR) signaling. This signaling is also important for initiation and progression of B-cell lymphoproliferative disorders. Bruton’s Tyrosine Kinase (BTK) is a member of the Tec family of kinases, downstream of the B-cell receptor and is predominantly expressed in B-cells. It is a mediator of B-cell receptor signaling in normal and transformed B-cells. Following binding of antigen to the B-Cell Receptor, kinases such as Syk (Spleen Tyrosine Kinase), Lyn (member of the Src family of protein tyrosine kinases) and BTK (Bruton’s Tyrosine Kinase) are activated, with subsequent propagation through PI3K/Akt, MAPK, and NF-κB pathways. This results in B-cell activation and proliferation. IMBRUVICA® (Ibrutinib) is an oral, irreversible inhibitor of BTK and inhibits cell proliferation and promotes programmed cell death (Apoptosis) by blocking B-cell activation and signaling. The FDA initially granted accelerated approval to IMBRUVICA® in February 2014 for previously treated patients with CLL and this was followed by full FDA approval and a new treatment indication for high-risk CLL patients with 17p deletions, in July 2014. Previously published studies had shown significant Response Rates and and Event-Free Survival with BR (Bendamustine-TREANDA® and Rituximab-RITUXAN®) in FLUDARA® (Fludarabine) refractory patients, with Chronic Lymphocytic Leukemia.

The HELIOS study is a double-blind, randomized, phase III trial which evaluated the benefit of combining IMBRUVICA® with BR compared to placebo plus BR, in patients with previously treated, relapsed/refractory Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma. In this study, of the 578 randomized patients, 289 patients received a maximum of six cycles of BR with IMBRUVICA® 420 mg PO daily and 289 patients received BR with placebo. The median patient age was 64 years, patients had received a median of two prior therapies and 38% of the patients had Rai Stage III/IV disease. Patients with 17p deletions in more than >20% of cells, were excluded. The planned six cycles of BR were completed by 83% in the IMBRUVICA® group and 78% in the placebo group. The primary endpoint was Progression Free Survival (PFS). Secondary endpoints included Overall Survival (OS) and Overall Response Rate (ORR). Following an interim analysis, this study was unblinded as there was a significant PFS benefit with IMBRUVICA® and patients receiving placebo, were allowed to cross over to the IMBRUVICA® group, per study protocol,. Thirty one percent (31%) of the patients in the BR plus placebo group with confirmed progressive disease crossed over to receive BR plus IMBRUVICA®. At a median follow up of 17.2 months, the PFS in the IMBRUVICA® plus BR group was not yet reached whereas the PFS was 13.3 months for patients receiving placebo plus BR (HR=0.203; P<0.0001). This PFS benefit was seen across subgroups of high-risk patients as well. The ORR was 82.7% in the IMBRUVICA® plus BR group compared to 67.8% in the placebo plus BR group (P <0.0001). Complete Response (CR) rates which included CR with incomplete blood count recovery were 10.4% versus 2.8% with IMBRUVICA® and placebo, respectively. The median OS was not reached. The incidence of most adverse events were comparable between the two treatment groups and the most frequent side effects were neutropenia affecting about 55% of the patients and nausea experienced by about 35% of the patients. The authors concluded that IMBRUVICA® plus BR resulted in an 80% reduction in the risk of disease progression, as well as improved Overall Response Rates, compared to placebo plus BR. This triplet combination of IMBRUVICA®, TREANDA® and RITUXAN® should therefore be considered an important treatment option for patients with previously treated Chronic Lymphocytic Leukemia and Small Lymphocytic Lymphoma. Ibrutinib combined with bendamustine and rituximab (BR) in previously treated chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL): first results from a randomized, double-blind, placebo-controlled, phase III study. Chanan-Khan AAA, Cramer P, Demirkan F, et al. J Clin Oncol. 2015;33 (suppl; abstr LBA7005).

Daily Aspirin May Improve Survival after Diagnosis of Colorectal Cancer

SUMMARY:The American Cancer Society estimates that approximately 133,000 new cases of ColoRectal Cancer (CRC) will be diagnosed in the United States in 2015 and close to 50,000 are expected to die of the disease. Several epidemiological studies as well as randomized controlled trials have shown that Aspirin reduces the incidence of ColoRectal Cancer (CRC) and CRC associated mortality. Platelets have long been implicated in the mechanism of tumor metastases. More recent data suggests that platelets may play a role in tumorigenesis as well, through the release of angiogenic and growth factors due to overexpression of COX-2. Daily low dose Aspirin inhibits COX-1 and COX-2. It is postulated that Aspirin also works by COX-independent mechanisms such as, the inhibition of NF-kB and Wnt/ β-catenin signaling, which may play a role in its chemopreventive properties. Even though the benefits of Aspirin in the primary prevention of CRC remains well established, the role of Aspirin in secondary prevention in patients with CRC is unclear. The authors conducted this trial to evaluate the association between Aspirin use after diagnosis of CRC with CRC-Specific Survival (CSS) and Overall Survival (OS) in the largest group of patients ever studied. The study authors in this retrospective study identified 25,644 patients in the Cancer Registry of Norway, diagnosed with ColoRectal Cancer (CRC) from 2004 through 2011. Using the Norwegian Prescription Database, the authors were then able to establish that 6,109 patients in this large cohort had documented exposure to Aspirin. Exposure to Aspirin was defined as a prescription for more than 6 months of Aspirin following a diagnosis of CRC. The median follow up was 2.2 years. The authors performed a multivariate regression analysis controlling for age, gender, tumor stage, tumor differentiation and noted that exposure to Aspirin post-diagnosis, independently improved ColoRectal Cancer (CRC) -Specific Survival (HR=0.75; P<0.001) and Overall Survival (HR=0.86; P<0.001). The authors concluded that in this large group of unselected ColoRectal Cancer (CRC) patients, exposure to Aspirin after the diagnosis of CRC is independently associated with improved Colorectal Cancer-Specific Survival and Overall Survival. They added that because of the risk of bleeding, the risk–benefit should be assessed before Aspirin is routinely recommended to this patient population. Impact of aspirin as secondary prevention in an unselected cohort of 25,644 patients with colorectal cancer: A population-based study. Bains S, Mahic M, Cvancarova M, et al. J Clin Oncol 33, 2015 (suppl; abstr 3504)

Late Breaking Abstract – ASCO 2015 ARIMIDEX® may be a Better Treatment Option Compared to Tamoxifen in Postmenopausal Women with DCIS

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, 231,840 new cases of invasive breast cancer will be diagnosed in 2015 and over 40,000 women will die of the disease.Estrogen Receptor (ER) positive breast cancer cells are driven by estrogens. Tamoxifen is a nonsteroidal Selective Estrogen Receptor Modulator (SERM) and works mainly by binding to the Estrogen Receptor and thus blocks the proliferative actions of estrogen on the mammary tissue. Anastrozole is a non-steroidal Aromatase Inhibitor that binds reversibly to the aromatase enzyme and inhibits the conversion of androgens to estrogens in the extra-gonadal tissues. Aromatase Inhibitors such as ARIMIDEX® have been proven to be superior to Tamoxifen, as adjuvant therapy, in postmenopausal patients with hormone receptor positive breast cancer. It was however not known whether ARIMIDEX® was superior to Tamoxifen in preventing the recurrence of breast cancer.

NSABP B-35 is a randomized phase III trial which compared ARIMIDEX® to Tamoxifen, in preventing the recurrence of breast cancer, in postmenopausal women with Ductal Carcinoma In Situ (DCIS), who underwent lumpectomy and radiation therapy. Of the 3,104 patients who were enrolled and randomized, 1552 patients received ARIMIDEX® 1 mg PO daily and 1552 patients received Tamoxifen 20 mg PO daily. Treatment was continued for 5 years. Enrolled patients had tumors with no invasive component, Estrogen or Progesterone Receptors were positive and margins of resection were clear. The primary endpoint was Breast Cancer-Free Interval (BCFI), defined as the time from randomization to any breast cancer event including local, regional, or distant recurrence or contralateral invasive cancer or DCIS. With a median follow up of 8.6 years, the 10 year Breast Cancer–Free Interval rates were 93.5% with ARIMIDEX® versus 89.2% with Tamoxifen, and this was statistically significant (HR=0.73, P=0.03). This benefit was more so in women less than 60 years of age, with a Breast Cancer–Free Interval rates of 94.9% with ARIMIDEX® and 88.2% with Tamoxifen (HR=0.52, P=0.003). However, in women over 60 years of age, there were no significant differences in outcomes noted between the ARIMIDEX® and Tamoxifen groups. The incidence of invasive contralateral breast cancer was reduced by 45% (HR=0.55, P=0.03) in the ARIMIDEX® group, compared to Tamoxifen group. Adverse events were less common with ARIMIDEX® compared to Tamoxifen. The authors concluded that for postmenopausal women with DCIS treated with lumpectomy and radiation, the 10 year Breast Cancer–Free Interval rates are significantly higher with 5 years of ARIMIDEX® than Tamoxifen and ARIMIDEX® may also be a consideration for those women, who are concerned about the risk of thromboembolic events and uterine cancer with Tamoxifen treatment. Primary results, NRG Oncology/NSABP B-35: A clinical trial of anastrozole (A) versus tamoxifen (tam) in postmenopausal patients with DCIS undergoing lumpectomy plus radiotherapy. Margolese RG, Cecchini RS, Julian TB, et al. J Clin Oncol 33, 2015 (suppl; abstr LBA500)

Late Breaking Abstract – ASCO 2015 Adjuvant Whole Brain Radiation Therapy Not Recommended After Stereotactic RadioSurgery

SUMMARY: Brain metastases from an extracranial primary, occur in approximately 15% of cancer patients and this is estimated to be about 400,000 to 600,000 patients annually. The incidence of brain metastases has been on the rise with the availability of more effective systemic therapies and better control of systemic disease. The most frequent malignancies associated with brain metastases include Lung cancer, Breast cancer and Melanoma. Majority of the patients with brain metastases have synchronous extracerebral metastases. A significant number of patients present with solitary or fewer than 3 brain metastases and they may be amenable to focal therapeutic interventions. However, Whole Brain Radiation Therapy (WBRT) has been the standard treatment strategy since the 1950’s. It is also well recognized that WBRT can be associated with neurocognitive dysfunction. Stereotactic RadioSurgery (SRS) is a non-surgical procedure that allows delivery of significantly higher doses of precisely focused radiation to the tumor, compared to conventional radiation therapy, with less collateral damage to the surrounding normal tissue. The technologies used for SRS include GAMMA KNIFE® which uses highly focused gamma rays, Proton Beam therapy which uses ionized hydrogen or Protons, Linear Accelerator and CYBER KNIFE® which use Photons, to target the tumor tissue.

NCCTG N0574 is a federally funded, randomized phase III clinical trial, designed to determine whether cognitive deterioration occurred less frequently with SRS alone compared to SRS followed by WBRT, in patients with 1-3 brain metastases. In this study, 213 patients with 1-3 brain metastases, each measuring less than 3 cm by contrast MRI, were enrolled and randomized to SRS alone or SRS plus WBRT. All patients underwent cognitive testing before and after treatment. Sixty eight percent (68%) of the enrolled patients had a Lung primary and the median age was 60 years. Baseline characteristics were similar in both treatment groups. The median follow up was 7.2 months. The authors used several tools to assess cognitive dysfunction and the primary endpoint was the cognitive decline at 3 months following treatment. It was noted that at 3 months, with the addition of WBRT to SRS, 91.7% of patients experienced cognitive decline compared with 63.5% for those receiving SRS alone (P=0.0007) and there was statistically significant decline in immediate recall, delayed recall and verbal fluency, in the SRS plus WBRT group. Patients who received SRS plus WBRT also reported significantly worse Quality of Life. There was however better intracranial tumor control at 6 and 12 months with SRS plus WBRT compared to SRS alone (P< 0.001), but this local control had no significant impact on the median Overall Survival (OS), with similar OS outcomes noted in both treatment groups (P=0.93). The authors concluded that the addition of WBRT to SRS can result in significant decline in neurocognitive function, without any Overall Survival benefit, compared to SRS alone. It is therefore recommended that patients with newly diagnosed brain metastases amenable to SRS, be closely monitored after SRS, with consideration given to WBRT, at the time of symptomatic progression. NCCTG N0574 (Alliance): A phase III randomized trial of whole brain radiation therapy (WBRT) in addition to radiosurgery (SRS) in patients with 1 to 3 brain metastases. Brown PD, Asher AL, Ballman KV, et al. J Clin Oncol 33, 2015 (suppl; abstr LBA4)

Late Breaking Abstract – ASCO 2015 OPDIVO® Improves Overall Survival in Non- Squamous NSCLC Patients

SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 27% of all cancer deaths. It is the leading cause of cancer death among both men and women. The American Cancer Society estimates that over 221,200 new cases of lung cancer will be diagnosed in the United States in 2015 and over 158,000 patients will die of the disease. Non Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of Non Small Cell Lung Cancer (NSCLC), 25% are Squamous cell carcinomas, 40% are Adenocarcinomas and 10% are Large cell carcinomas. The treatment paradigm for solid tumors has been rapidly evolving with a better understanding of the Immune checkpoints. Immune checkpoints are cell surface inhibitory proteins/receptors that are expressed on activated T cells. They harness the immune system and prevent uncontrolled immune reactions. Survival of cancer cells in the human body may be to a significant extent, related to their ability to escape immune surveillance, by inhibiting T lymphocyte activation. The T cells of the immune system therefore play a very important role in modulating the immune system. Under normal circumstances, inhibition of an intense immune response and switching off the T cells of the immune system, is an evolutionary mechanism and is accomplished by Immune checkpoints or gate keepers. With the recognition of Immune checkpoint proteins and their role in suppressing antitumor immunity, antibodies are being developed that target the membrane bound inhibitory Immune checkpoint proteins/receptors such as CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4), also known as CD152, PD-1(Programmed cell Death-1), etc. By doing so, one would expect to unleash the T cells, resulting in T cell proliferation, activation and a therapeutic response. The first Immune checkpoint protein to be clinically targeted was CTLA-4. YERVOY® (Ipilimumab) , an antibody that blocks Immune checkpoint protein/receptor CTLA- 4, has been shown to prolong overall survival in patients with previously treated, unresectable or metastatic melanoma. OPDIVO® (Nivolumab) is a fully human, immunoglobulin G4 monoclonal antibody that binds to the PD-1 receptor and blocks its interaction with PD-L1 and PD-L2, thereby undoing PD-1 pathway-mediated inhibition of the immune response and unleashing the T cells. The U. S. Food and Drug Administration granted approval to OPDIVO®, for the treatment of patients with metastatic Squamous Non-Small Cell Lung Cancer (NSCLC), with progression on or after platinum based chemotherapy. CheckMate 057 is a randomized, international, phase 3 study designed to evaluate the benefit of OPDIVO® for patients with Non-Squamous (NSQ) NSCLC who had progressed after platinum-based doublet chemotherapy. A total of 582 patients were randomized to receive OPDIVO® 3 mg/kg IV every 2 weeks (n=292) or TAXOTERE® 75 mg/m2 IV every 3 weeks (n=290). Eligible patients included those with advanced Non-Squamous NSCLC who had progressed after platinum-based doublet chemotherapy and a Tyrosine Kinase Inhibitor (TKI), if deemed eligible for a TKI. Treatment was continued until disease progression or unacceptable toxicity. The primary clinical endpoint was Overall Survival (OS). Secondary endpoints included Objective Response Rate (ORR), Progression Free Survival (PFS), Efficacy based on PD-L1 expression, Quality of Life, and Safety. The study was stopped earlier than expected following assessment by the independent Data Monitoring Committee (DMC) which concluded that the study met its endpoint, demonstrating superior overall survival, in patients receiving OPDIVO®, compared to the control group. Patients in the OPDIVO®, group had a significantly higher median OS compared to those in the TAXOTERE® group (12.2 months versus 9.4 months, Hazard Ratio [HR] 0.73, P=0.0015). This meant a 27% reduction in the risk of death in the OPDIVO® group and this survival benefit was seen in all predefined subgroup of patients. The Objective Response Rate (ORR) was also significantly higher for patients receiving OPDIVO® compared to TAXOTERE® (19% versus 12%, P=0.0246) and the median duration of response (DOR) was significantly higher for the OPDIVO® group (17.2 months) vs the TAXOTERE® group (5.6 months). More importantly, when tumor PD-L1 expression was correlated with Overall Survival, the median OS for OPDIVO® was 17.2 months, 18.2 months, and 19.4 months for patients with tumors having 1% or higher, 5% or higher, and 10% or higher of cells staining positive for PD-L1, respectively, compared with 9.0 months, 8.1 months, and 8.0 months with TAXOTERE® treatment. Even though this study showed significant survival outcomes for patients expressing any level of PD-L1, the magnitude of benefit was even more so, in patients with tumors expressing higher levels of PD-L1. PD-L1 expression may therefore be a predictor of response, although this should not yet be used for patient selection. Grade 3-5 adverse events occurred more often in the TAXOTERE® group compared to the OPDIVO® group (54% vs 10%). Based on this compelling data, the authors concluded that OPDIVO® significantly improves Overall Survival when compared to TAXOTERE®, in patients with advanced non-Squamous NSCLC, after failure of platinum based doublet therapy. Phase III, randomized trial (CheckMate 057) of nivolumab (NIVO) versus docetaxel (DOC) in advanced non-squamous cell (non-SQ) non-small cell lung cancer (NSCLC). Paz-Ares L, Horn L, Borghaei H, et al. J Clin Oncol 33, 2015 (suppl; abstr LBA109)</s

Role of Radiotherapy in Elderly Patients with Low Risk Breast Cancer Following Breast Conserving Surgery

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, 231,840 new cases of invasive breast cancer will be diagnosed in 2015 and over 40,000 women will die of the disease. The National Surgical Adjuvant Breast and Bowel Project (NASBP) protocols B-04 and B-06 have clearly established, after more than a 2 decades of evaluation and follow up that, in Stage I and II breast cancer, there is no significant difference in either distant Disease Free or Overall Survival between the breast conserving surgery and breast removal surgery (Mastectomy). This data established breast-sparing surgery as the preferred local-regional procedure. Radiotherapy after breast-conserving surgery significantly decreases the risk of local recurrence and improves breast cancer–specific survival in certain subgroups of patients. Under ideal circumstances, approximately 70% of the patients can be treated with breast conserving surgery and the risk factors for local recurrences include younger age, high tumor grade, negative hormone receptor status, lymphovascular invasion, extensive intraductal component and positive surgical margins. According to the American Cancer Society, 42% of all invasive breast cancers in the US occur in women 65 years of age or older. These patients may have associated comorbidities and may therefore be appropriate candidates for breast-sparing surgery (rather than mastectomy), as post-op recovery time is shorter. Elderly patients often present with breast tumors that are hormone receptor positive and indolent. Whether women 70 years of age or older with early stage breast cancer need radiotherapy after breast conserving surgery, was addressed by the CALGB cooperative group ( CALGB 9343) and it was noted that the addition of radiation did not improve Overall Survival or distant Disease Free Survival, although there was some improvement in locoregional recurrence rate.

The authors in PRIME II study evaluated local control outcomes in elderly women with early stage breast cancer, at low risk of local recurrence at 5 years, by avoiding whole-breast radiotherapy, following breast conserving surgery. In this Phase III randomized trial, 1326 patients 65 years or older, with low risk early breast cancer, who had undergone breast conserving surgery and were receiving adjuvant hormonal treatment, were randomly assigned to receive whole-breast irradiation (N=658) or no further therapy (N=668). Low risk was defined as tumors T1–T2 up to 3 cm in greatest dimension, clear surgical margins, negative axillary nodes and positive hormone receptors. Either lymphovascular invasion or grade 3 tumor histology was permitted, but not both. The primary endpoint was ipsilateral breast tumor recurrence. After median follow up of 5 years, ipsilateral breast tumor recurrence was 1.3% in women assigned to whole-breast radiotherapy and 4.1% in those assigned no radiotherapy (P=0•0002). There was however no differences in regional recurrence, contralateral breast cancers, distant metastases or new breast cancers, noted between the two groups. The 5-year Overall Survival was similar in both groups 93•9% (P=0•34). The authors concluded that the 5-year ipsilateral breast tumor recurrence is probably low enough that radiotherapy could be avoided in a subset of elderly patients with low risk breast cancer following breast conserving surgery. Kunkler IH, Williams LJ, Jack WJ, et al: Breast-conserving surgery with or without irradiation in women aged 65 years or older with early breast cancer (PRIME II): A randomised controlled trial. Lancet -Oncol. 2015;16:266-273

Monoclonal Antibody Combination Significantly Improves Progression Free Survival in Relapsed and Refractory Multiple Myeloma

SUMMARY: Multiple Myeloma is a clonal disorder of plasma cells in the bone marrow and the American Cancer Society estimates that in the United States, close to 27,000 new cases will be diagnosed in 2015 and 11,240 will die of the disease. REVLIMID® (Lenalidomide) given along with weekly Dexamethasone, was associated with significantly improved Progression Free Survival (PFS) when administered until disease progression, in patients with newly diagnosed Multiple Myeloma. This combination of REVLIMID® and weekly Dexamethasone is considered a reference regimen (Control arm) for both newly diagnosed and relapsed Multiple Myeloma. Elotuzumab (HuLuc63) is a monoclonal antibody that binds to the Signal Lymphocyte Activation Molecule – SLAMF7 protein (CS1, CD319), which is highly expressed on Myeloma cells and also expressed on Natural Killer (NK) lymphocytes in the immune system. By virtue of its dual mechanism of action, it targets and destroys Myeloma cells and also enhances the activation of Natural Killer cells. Previously published phase Ib/II study, has shown encouraging activity, when Elotuzumab was combined with REVLIMID® and Dexamethasone, in patients with Relapsed/Refractory Multiple Myeloma (RRMM). ELOQUENT-2 is an open-label phase III trial in which 646 patients with Relapsed/Refractory Multiple Myeloma were randomized in a 1:1 ratio to receive Elotuzumab in combination with REVLIMID® and Dexamethasone (N=321) or REVLIMID® and Dexamethasone alone (N=325). Enrolled patients had 1–3 prior therapies and were not REVLIMID® refractory. Prior therapies included VELCADE® (Bortezomib), THALOMID® (Thalidomide) and REVLIMID®. Approximately 35% of the enrollees were refractory to the last therapy, 32% had del(17p) and 9% had t(4;14). The median age was 66 years. Elotuzumab was administered at 10 mg/kg IV weekly for the first two cycles and then once every 2 weeks thereafter. REVLIMID® was given at 25 mg orally on days 1 thru 21 of each cycle along with Dexamethasone 40 mg weekly. In the Elotuzumab group, Dexamethasone was dosed at 28 mg orally plus 8 mg IV on the weeks when Elotuzumab was administered. The cycle duration was 28 days. Treatment was administered until disease progression or unacceptable toxicity. Primary endpoints were Progression Free Survival (PFS) and Overall Response Rate (ORR). At a median follow up of 24 months, PFS in the Elotuzumab group was 19.4 months compared to 14.9 months in the REVLIMID®/Dexamethasone alone group (HR=0.70; P=0.0004). The 1-year PFS for the Elotuzumab versus control group was 68% vs 57% respectively and the 2-year PFS was 41% vs 27%. This benefit was seen across all subgroups including those with unfavorable cytogenetics. The ORR was 79% in the Elotuzumab group and 66% in the control group. (P = 0.0002). At the time of this interim analysis, more patients in the Elotuzumab group remained on therapy (35%) compared to the control group (21%) and treatment discontinuation was mainly for disease progression. Grade 3–4 toxicities occurred in 15% or more patients in the Elotuzumab group and included neutropenia and anemia. The authors concluded that Elotuzumab with its novel immunotherapeutic mechanism of action, when added to REVLIMID® and Dexamethasone, reduced the risk of disease progression by 30% in patients with Relapsed/Refractory MultipleMyeloma, and this was accomplished with manageable toxicities. Patients in this study are being followed up for long term outcomes including Overall Survival. Lonial S, Dimopoulos MA, Palumbo A, et al. ELOQUENT-2: A phase III, randomized, open-label study of lenalidomide (Len)/dexamethasone (dex) with/without elotuzumab (Elo) in patients (pts) with relapsed/refractory multiple myeloma (RRMM). J Clin Oncol. 2015;(suppl; abstr 8508).</s

Higher Risk of Fractures in Hematopoietic Stem Cell Transplant Recipients

SUMMARY: According to the CIBMTR (Center for International Blood and Marrow Transplant Research), in 2012, over 11,000 Hematopoietic Stem Cell Transplants (HSCT) in the US were Autologous and over 7500 were Allogeneic. Multiple myeloma and Lymphoma accounted for 57% of all HSCTs and AML and Myelodysplasia accounted for 51% of Allogeneic HSCTs. There has been an increase in the number of Autologous and Allogeneic transplants for treatment of malignant diseases in elderly patients, with 39% of Autologous transplant recipients and 17% of Allogeneic transplant recipients between 2006-2012 reported to be older than 60 years of age. With increase in the number of long term survivors following transplantation, early and late complications of HSCT have been the focus of increasing attention. Morbidity and mortality as well as quality of life related to bone loss among long term survivors after HSCT, has been previously published. Factors contributing to bone loss in this patient population include intensive chemotherapy, total body irradiation, post-transplantation glucocorticoid use, reduced intake and metabolism of Calcium and Vitamin D, graft versus host disease, use of Cyclosporine-A and sedentary lifestyle after transplantation. Loss of Bone Mineral Density (BMD) occurs within 6 to 12 months after transplantation at all skeletal sites, followed by initial recovery of BMD in the lumbar spine and a slower recovery of BMD in the femur neck. This bone loss may persist for 48 to 120 months or even longer. The authors in this single institution, retrospective study, calculated the cumulative incidence rates of fractures among survivors of Autologous and Allogeneic Hematopoietic Stem Cell Transplantations (HSCT) and compared the rate of fractures to that of the general US population. Data was collected from 7,620 patients over 18 years of age who underwent HSCT at The University of Texas MD Anderson Cancer Center, from January 1997 to December 2011 and these patients were observed through December 2013. The authors then calculated the cumulative incidence of fractures, with death as a competing risk and the age and sex-specific fracture incidence rates were compared with those in the US general population, using estimated rates from the 1994 National Health Interview Survey and the 2004 National Hospital Discharge Survey. Of the 7,620 patients who underwent HSCT, 56% were male and 51% underwent Autologous and 49% underwent Allogeneic stem cell transplantation. The most common reasons for HSCT were hematologic malignancies other than Multiple Myeloma (67%), Multiple Myeloma (22%) and other solid tumors (11%). The median follow up was 85 months. Fractures occurred in 8% of patients (N = 602) of whom 419 patients had an Autologous stem cell transplantation and 183 patients had Allogeneic stem cell transplantation. The incidence of fracture was higher in patients older than age 50 years, 5 times higher among patients with Multiple Myeloma compared to other hematologic malignancies and patients who underwent Autologous transplantation were 45% more likely to develop a fracture than those who underwent an Allogeneic transplantation. When age- and sex-specific fracture incidence rates after HSCT were compared with National Health Interview Survey data, females were at approximately 8 times greater risk and men 45-64 years old were at approximately 7-9 times greater risk of sustaining a fracture. The authors concluded that the incidence of fractures after HSCT is significantly higher and all patients undergoing HSCT should be considered to be at risk for post-transplantation bone loss. Measures to prevent bone loss and fractures include physical exercise, Vitamin D and Calcium supplementation, avoiding tobacco products, abstaining from excess alcohol intake and fall prevention. The authors recommend that patients undergoing HSCT should have a Dual Energy X-ray Absorptiometry scan performed at baseline and at 6 months following transplantation. Increased Incidence of Fractures in Recipients of Hematopoietic Stem-Cell Transplantation. Pundole XN, Barbo AG, Lin H, et al. J Clin Oncol 2015; 33:1364-1370

Dual Vaccine Therapy for Metastatic Pancreatic Cancer Improves Overall Survival

SUMMARY: The American Cancer Society estimates that in 2015, close to 49,000 people will be diagnosed with Pancreatic Cancer in the United States and over 40,000 people will die of the disease. Some important risk factors for Pancreatic Cancer include increasing age, obesity, smoking history, genetic predisposition, exposure to certain dyes and chemicals, heavy alcohol use and pancreatitis. The best chance for long term survival is complete surgical resection, although this may not be feasible in a majority of the patients, as they present with advanced disease at the time of diagnosis. Based on the National Cancer Data Base, the 5 year observed survival rate for patients diagnosed with exocrine cancer of the pancreas is 14% for those with Stage IA disease and 1% for those with Stage IV disease. The FDA recently granted Breakthrough Therapy Designation status for the combination treatment that consists of two vaccines, GVAX and CRS-207, for patients with advanced Pancreatic Carcinoma. This designation was based on a phase II clinical trial in which the authors took a novel approach and tested a combination of two vaccines in patients with metastatic Pancreatic Adenocarcinoma. Traditional vaccination against specific bacterial and viral infections involves the injection of the specific weakened bacteria/virus or a structural component of the bacteria or virus. The body then mounts an immune response and is ready to respond to an infection associated with that specific bacteria or virus. Use of vaccines in cancer treatment is based on the same principle. The two vaccines studied were GVAX and CRS-207. GVAX is an allogeneic whole cell vaccine developed from Pancreatic Cancer cell lines. These cancer cells are irradiated, to prevent them from dividing and are genetically modified to secrete GM-CSF (Granulocyte Macrophage Colony Stimulating Factor). GM-CSF is important for the growth and activation of dendritic cells also known as Antigen Presenting Cells. This vaccine when injected attracts the dendritic cells to the vaccine injection site and the dendritic cells in turn, pick up the antigens from the vaccine and present them to the patient’s immune system. The immune system then mounts a response by activating tumor specific T-cells. This vaccine therefore theoretically boosts the body’s immune system to fight the patient’s tumor, without causing collateral damage. The second vaccine CRS-207 is live-attenuated (weakened) Listeria monocytogenes bacterium which expresses mesothelin and stimulates innate and adaptive immunity. It is genetically engineered to elicit an immune response against the tumor-associated antigen mesothelin, which has been shown to be expressed at higher levels on Pancreatic Cancer cells than on normal cells. Previous studies have demonstrated that survival can be improved by induction of mesothelin specific T-cell responses. In this study, 90 patients with metastatic Pancreatic Adenocarcinoma were randomly assigned in a 2:1 ratio to receive two doses of GVAX followed by four doses of CRS-207 in Group A and six doses of GVAX alone in the Group B. Treatment was given every 3 weeks and low-dose CYTOXAN® (Cyclophosphamide) was given IV, the day before GVAX in both groups, to inhibit regulatory (suppressive) T-cells. More than 80% of the patients had at least one prior treatment for metastatic disease and 50% had two or more prior treatments. The Primary endpoint was overall survival. Secondary endpoints included safety, clinical and immune responses. At a planned interim analysis, the median Overall Survival (OS) was 6.1 months in Group A patients who had received the combination of two vaccines compared to 3.9 months in Group B patients who received GVAX alone (HR=0.59, P=0.02), resulting in a 41% reduction in risk of death with the combination immunotherapy. The one year survival probability doubled with the dual vaccine with an estimated one year survival of 24% for the combination immunotherapy group (Group A) compared with 12% for the GVAX alone group (Group B). The median OS in an updated analysis of patients who received three total doses which included at least two doses of GVAX and at least one dose of CRS-207 was 9.7 months compared to 4.6 months for those who received three doses of GVAX alone (HR=0.53, P=0.02), a 47% reduction in the risk of death. In the subgroup of patients who had two or more prior chemotherapy regimens, combination immunotherapy given as third line therapy or greater resulted in a median OS of 5.7 months compared to 3.7 months with GVAX alone (HR=0.30, P<0.001), a 70% reduction in risk of death. Stabilization or reduction of tumor marker CA 19-9, was seen in 27% of patients receiving combination immunotherapy compared to 9% in those who received GVAX alone (P=0.08). The median OS in patients with stable or better CA 19-9 response was 10.3 months compared with 4 months in those with CA 19-9 progression (HR=0.43, P=0.02). Toxicities included local reactions after GVAX and transient fevers, chills, and lymphopenia after CRS-207 administration. The authors concluded that immunotherapy with a combination of two vaccines improved Overall Survival with minimal toxicity, for patients with metastatic Pancreatic Carcinoma, who had failed prior therapies. Safety and Survival With GVAX Pancreas Prime and Listeria Monocytogenes–Expressing Mesothelin (CRS-207) Boost Vaccines for Metastatic Pancreatic Cancer. Le DT, Wang-Gillam A, Picozzi V, et al. J Clin Oncol 2015; 33:1325-1333