SUMMARY: The FDA on November 20, 2015, approved NINLARO® (Ixazomib) in combination with REVLIMID® (Lenalidomide) and Dexamethasone for the treatment of patients with Multiple Myeloma who have received at least one prior therapy. 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. Proteasomes are enzymes found in cells and they enable the breakdown of abnormal or mutant proteins. The amino acids from these proteins are recycled to make new proteins. Myeloma cells depend on the proteasomes to facilitate this metabolic function, to regulate their growth and survival. NINLARO® (Ixazomib) unlike VELCADE® (Bortezomib), is a second generation, oral, proteasome inhibitor, which disrupts protein metabolism in Myeloma cells, by inhibiting proteasomes and has an antiproliferative and pro-apoptotic effect.
The approval of NINLARO® was based a pivotal, multicenter, randomized, double-blind, placebo-controlled, phase III trial (TOURMALINE-MM1 study), in which 722 patients with Multiple Myeloma were randomized in a 1:1 ratio to receive either a combination of NINLARO®, REVLIMID® and Dexamethasone (N=360) or a combination of Placebo, REVLIMID® and Dexamethasone (n=362). NINLARO® was administered at 4 mg PO on days 1, 8, and 15 in combination with REVLIMID® 25 mg PO on days 1 thru 21 and Dexamethasone 40 mg PO on days 1, 8, 15, and 22 of a 28 day treatment cycle. Treatment was continued until disease progression or unacceptable toxicity. Enrolled patients had received 1 to 3 prior lines of therapy, which included VELCADE® (69%), THALOMID® (45%), and REVLIMID® (12%) and 77% of the patients had relapsed Multiple Myeloma. The median age of patients was 66 years. The primary end point of the study was Progression Free survival (PFS) and secondary endpoints included Objective Response Rate (ORR), safety, and Overall Survival.
At a prespecified interim analysis, the median PFS with the combination arm of NINLARO®, REVLIMID® and Dexamethasone was 20.6 months compared with 14.7 months for the combination group of Placebo, REVLIMID® and Dexamethasone (HR= 0.74, P=0.012).Secondary end points data was not mature at the time of this analysis. Patients in the NINLARO® group experienced more adverse events which included cytopenias, vomiting, diarrhea, peripheral neuropathy and skin rash.
The authors concluded that NINLARO® based oral triplet therapy significantly prolonged Progression Free Survival compared with REVLIMID® and Dexamethasone, with acceptable toxicities. Studies are underway, evaluating NINLARO® in newly diagnosed Myeloma patients as well as maintenance therapy in non-transplant patients. Ixazomib, an Investigational Oral Proteasome Inhibitor (PI), in Combination with Lenalidomide and Dexamethasone (IRd), Significantly Extends Progression-Free Survival (PFS) for Patients (Pts) with Relapsed and/or Refractory Multiple Myeloma (RRMM): The Phase 3 Tourmaline-MM1 Study (NCT01564537). Moreau P, Masszi T, Grzasko N, et al. 2015 ASH Annual Meeting; Orlando, FL; December 5-8, 2015. Abstract 727.
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
To briefly summarize the structure of a chromosome, individual loops of coiled double-helix DNA wrap around a histone protein to form a nucleosome. Nucleosomes are then coiled together to form chromatin fibers, which looks like beads on a string. The chromatin fibers are coiled even more tightly to form chromosomes. HDAC enzymes catalyze the removal of acetyl groups and regulate the level of acetylation of the histones and non-histone proteins and transcription of several genes. Hypoacetylation of histones has been associated with a condensed chromatin structure that results in the repression of gene transcription, whereas acetylated histones are associated with a more open chromatin structure and activation of gene transcription. HDACs are grouped into four major classes (Class I, II, III and IV) and regulate cell-cycle progression, cell survival, angiogenesis and immunity. The HDAC Class I enzymes are HDAC1, 2, 3 & 8 and are typically found in the nucleus where they are able to repress transcription. The HDAC Class II enzymes include HDAC4, 5, 6, 7, 9 and 10 and are able to move between the cytoplasm and nucleus and function in signal transduction. In Multiple Myeloma, the important enzyme to target is HDAC6.
FARYDAK® is an oral, pan-histone deacetylase inhibitor which inhibits cell cycle progression and ultimately results in apoptosis. FARYDAK® inhibits the aggresome pathway of protein degradation which is upregulated when proteosome pathway is inhibited by VELCADE®. Based on preclinical data demonstrating synergy between VELCADE® and FARYDAK® in Myeloma, the PANORAMA 1 trial, enrolled patients with relapsed or refractory Multiple Myeloma who had received one to three prior lines of therapy and were not VELCADE® refractory. In this phase III trial, patients were randomly assigned to receive either FARYDAK® (N=387) or placebo (N=381), each along with IV VELCADE® and oral Dexamethasone. In this study, treatment was given in two 24 week phases. The first 24 week treatment phase was cycles 1 thru 8, where patients received placebo or FARYDAK® 20 mg orally QD 3 times a week for 2 weeks of a 3 week cycle; VELCADE® 1.3 mg/m2 IV twice weekly for 2 weeks of a 3 week cycle and Dexamethasone 20 mg PO on the day of and day after VELCADE®. Patients with clinical benefit (defined as complete response, partial response or stable disease, without significant toxicities) after the first eight cycles could proceed to the second phase of treatment in which FARYDAK® and Dexamethasone administration schedule remained the same but VELCADE® was administered once weekly for 2 weeks of the 3 week cycle. The median age was 63 years, 48% of patients had received at least two lines of therapy and 57% of patients had prior autologous stem cell transplantation and 43% had prior therapy with VELCADE®. The primary endpoint was Progression Free Survival (PFS) and secondary endpoints included Overall Survival (OS), Overall Response Rate (ORR), near Complete/Complete Response (nCR/CR) rate, Duration of Response (DOR), and safety. Among the patients enrolled in the FARYDAK® group (N = 387), 44% completed first phase of treatment and 26% completed the second phase of treatment. After a median follow up of 28 months, the primary end point of the study was met with a 37% decrease in the risk of disease progression in all the FARYDAK® group of patients compared to the placebo group (12 months vs 8.1 months, HR=0.63, P<0.0001). The median PFS was 14.65 months for those in the FARYDAK® group who completed the first phase of treatment and 17.64 months for those who completed the second phase of treatment. With regards to the secondary endpoints in the FARYDAK® vs placebo groups, the ORR was 60.7% vs 54.6% (P=0.87), nCR/CR rate was 27.6% vs 15.7% (P=0.00006), median duration of response was13.1months vs 10.9 months and median time to progression was 12.7 months vs 8.5 months respectively. It was noted that the nCR/CR rate was 52.9% for those patients who completed the second phase of treatment. The most common grade 3/4 adverse events in the FARYDAK® vs placebo arms included thrombocytopenia (67% vs 31%), neutropenia (35% vs 11%), and diarrhea (26% vs 8%) and these toxicities were manageable with dose reduction and supportive care. The authors concluded that a combination of FARYDAK®, VELCADE® and Dexamethasone significantly improves Progression Free Survival in patients with relapsed and refractory Multiple Myeloma, with manageable toxicities. Miguel JS, Hungria VTM , Yoon S, et al. 56th ASH Annual Meeting and Exposition, 2014. Abstract#4742
To briefly summarize the structure of a chromosome, individual loops of coiled double-helix DNA wrap around a histone protein to form a nucleosome. Nucleosomes are then coiled together to form chromatin fibers, which looks like beads on a string. The chromatin fibers are coiled even more tightly to form chromosomes. HDAC enzymes catalyze the removal of acetyl groups and regulate the level of acetylation of the histones and non-histone proteins and transcription of several genes. Hypoacetylation of histones has been associated with a condensed chromatin structure that results in the repression of gene transcription, whereas acetylated histones are associated with a more open chromatin structure and activation of gene transcription. HDACs are grouped into four major classes (Class I, II, III and IV) and regulate cell-cycle progression, cell survival, angiogenesis and immunity. The HDAC Class I enzymes are HDAC1, 2, 3 & 8 and are typically found in the nucleus where they are able to repress transcription. The HDAC Class II enzymes include HDAC4, 5, 6, 7, 9 and 10 and are able to move between the cytoplasm and nucleus and function in signal transduction. In Multiple Myeloma, the important enzyme to target is HDAC6. Panobinostat is an oral, pan-histone deacetylase inhibitor which inhibits cell cycle progression and ultimately results in apoptosis. Panobinostat inhibits the aggresome pathway of protein degradation which is upregulated when proteosome pathway is inhibited by VELCADE®.
Based on preclinical data demonstrating synergy between VELCADE® and Panobinostat in Myeloma, the PANORAMA 1 trial, enrolled patients with relapsed or refractory multiple myeloma who had received one to three prior lines of therapy and were not VELCADE® refractory. In this phase III trial, patients were randomly assigned to receive either Panobinostat (N=387) or Placebo (N=381), each along with IV VELCADE® and oral Dexamethasone. For cycles 1 thru 8, patients received Panobinostat 20 mg PO or Placebo on days 1, 3, 5, 8, 10, and 12; VELCADE® 1.3 mg/m2 IV on days 1, 4, 8, and 11; and Dexamethasone 20 mg PO on days 1-2, 4-5, 8-9, and 11-12 of a 21 day cycle. Patients with clinical benefit after the first eight cycles could proceed to the second phase of treatment in which VELCADE® was administered only on D1 and D8 and Dexamethasone administered only on days 1-2 and 8-9. The median age was 63 years, 48% of patients had received at least two lines of therapy and 57% of patients had prior autologous stem cell transplantation and 43% had prior therapy with VELCADE®. The primary endpoint was Progression Free Survival (PFS) and secondary endpoints included Overall Survival (OS), Overall Response Rate (ORR), near Complete/Complete Response (nCR/CR) rate, Duration of Response (DOR), and safety. After a median follow up of 28 months, the primary end point of the study was met with a 37% decrease in the risk of disease progression in the Panobinostat group compared to the Placebo group (12 months vs 8.1 months, HR=0.63, P<0.0001). With regards to the secondary endpoints in the Panobinostat vs Placebo groups, the ORR was 60.7% vs 54.6% (P=0.87), nCR/CR rate was 27.6% vs 15.7% (P=0.00006), median duration of response was13.1months vs 10.9 months and median time to progression was 12.7 months vs 8.5 months respectively. The most common grade 3/4 adverse events in the Panobinostat vs Placebo arms included thrombocytopenia (67% vs 31%), neutropenia (35% vs 11%), and diarrhea (26% vs 8%) and these toxicities were manageable with dose reduction and supportive care. The authors concluded that a combination of Panobinostat, VELCADE® and Dexamethasone significantly improves Progression Free Survival in patients with relapsed and refractory Multiple Myeloma, with manageable toxicities. Richardson PG, Hungria VTM , Yoon S, et al. J Clin Oncol 32:5s, 2014 (suppl; abstr 8510)</s
To address this controversy, the authors conducted a pooled analysis of the outcomes of two randomized phase III trials, designed to compare Continuous Treatment to Fixed Duration Therapy. In trail RVMM209, patients were randomized to either induction with Lenolidomide (REVLIMID®), followed by consolidation and subsequent maintenance with REVLIMID® (Continuous Treatment) or Fixed Duration Therapy which entailed REVLIMID® based induction followed by consolidation but no maintenance therapy. In Trial GIMEMA0305, the randomization was between Bortezomib (VELCADE®) based induction followed by maintenance treatment (Continuous Treatment) and VELCADE® induction, with no maintenance treatment (Fixed Duration Therapy). The trial investigators assessed PFS1 as the time from diagnosis to the occurrence of 1st relapse, PFS2 as time from diagnosis to the occurrence of 2nd relapse and Overall Survival as time from diagnosis to death , incorporating the duration of both 1st and 2nd remission. They then evaluated, both PFS1, PFS2 and OS in newly diagnosed multiple myeloma patients who received Continuous Therapy or Fixed Duration Therapy. In this pooled analysis 452 patients received Continuous Treatment and 461 patients received Fixed Duration Therapy .The median follow up was 52 months. Patients receiving Continuous Treatment had significantly prolonged PFS1 (median 35 months vs 24 months, HR 0.58; P<0.0001), PFS2 (median 63 months vs 47 months, HR 0.69, P=0.0001) and OS (median not reached [NR] vs 70 months, HR 0.70, P=0.0019), when compared with Fixed Dose Therapy. The authors evaluated the PFS and OS from first relapse to second relapse and from first relapse to death respectively, and they noted that the outcomes were similar among patients who received Continuous Treatment or Fixed Dose Therapy following initial diagnosis. The authors concluded that Continuous Treatment significantly improved PFS1, PFS2, and OS and findings from this pooled analysis suggested that the clinical benefit observed during first remission was not negated by a shorter second remission and Continuous Treatment did not induce tumor resistance. Continuous Treatment may be essential, as patients with multiple myeloma will always have some residual disease. It should be noted that certain institutions including the Mayo Clinic cap Continuous/Maintenance treatment at approximately 2 years, due to the lack of randomized comparative data, on the value of prolonged maintenance beyond 2 years. Palumbo A, Gay F, Musto P, et al. J Clin Oncol 32:5s, 2014 (suppl; abstr 8515)