Impact of Treatment Sequencing on Overall Survival in Patients with Transplant-Ineligible Newly Diagnosed Myeloma.

BACKGROUND: Because patients with newly diagnosed multiple myeloma (NDMM) do not always receive any treatment beyond first-line (1L) therapy, it is imperative that patients receive the best treatment in the 1L setting. However, the optimal initial treatment remains to be identified. We performed a clinical simulation to assess potential outcomes with different treatment sequences. PATIENTS AND METHODS: We used a partitioned survival model to compare overall survival (OS) with (1) daratumumab, lenalidomide, and dexamethasone (D-Rd) in 1L followed by a pomalidomide- or carfilzomib-based regimen in second line (2L) versus (2) bortezomib, lenalidomide, and dexamethasone (VRd) in 1L followed by a daratumumab-based regimen in 2L versus (3) lenalidomide and dexamethasone (Rd) in 1L followed by a daratumumab-based regimen in 2L. Probabilities of transition between health states (1L, 2L+, and death) were based on published clinical data and real-world data from the Flatiron Health database. The proportion of patients discontinuing treatment after 1L (attrition rates) in the base case was estimated with a binomial logistic model using data from the MAIA trial. RESULTS: Using D-Rd in 1L conferred a longer median OS compared with delaying daratumumab-based regimens until 2L after VRd or Rd, respectively (8.9 [95% CrI 7.58-10.42] vs. 6.92 [5.92-8.33] or 5.75 [4.50-7.25] years). Results of scenario analyses were consistent with the base case. CONCLUSION: Our simulation, which incorporates clinically representative treatments and attrition rates, supports the use of D-Rd as initial therapy, rather than delaying the use of daratumumab until later lines of therapy, in patients with transplant-ineligible NDMM.

Systematic Review and Meta-Analysis of Correlation of Progression-Free Survival-2 and Overall Survival in Solid Tumors.

Background: Using progression-free survival (PFS)2, time from randomization to 2nd disease progression or death, is proposed as a surrogate for overall survival (OS) in oncology clinical trials. We used published data from solid tumor trials to assess whether PFS2 and OS are correlated. Methods: A literature search identified studies that reported PFS, PFS2, and OS. Two reviewers screened for eligibility, and documented PFS2, PFS or time from 1st to 2nd disease progression or death and OS. Correlation between PFS2 and OS was assessed using: (1) Kendall's Tau + Pearson's correlation coefficient in randomized controlled trials (RCTs); (2) Meta-analysis with the random effects model to compute the pooled correlation of PFS2 and OS. Results: Overall, 133 studies met search criteria, 15 (28 arms) had complete PFS2 and OS data in ovarian, gastric, colorectal, prostate, lung, renal and breast cancers. A positive correlation for PFS2 and OS was found for all 15 studies (Kendall's Tau = 0.7 [95% CIs 0.54, 0.78]); 10 RCTs (Pearson's correlation coefficient = 0.86); and meta-analysis from 7 trials (pooled Spearman's correlation coefficient = 0.84 [p = 0.0001; 95% CIs 0.71, 0.96]). Conclusions: In this retrospective analysis PFS2 strongly correlates with OS supporting the use of PFS2 to measure long-term clinical benefit when OS cannot be assessed.

Outcomes in 370 patients with mantle cell lymphoma treated with ibrutinib: a pooled analysis from three open-label studies.

Ibrutinib is highly active in treating mantle cell lymphoma (MCL), an aggressive B-cell lymphoma. We pooled data from three ibrutinib studies to explore the impact of baseline patient characteristics on treatment response. Patients with relapsed/refractory MCL (n = 370) treated with ibrutinib had an objective response rate (ORR) of 66% (20% complete response; 46% partial response); median duration of response (DOR), progression-free survival (PFS) and overall survival (OS) were 18·6, 12·8 and 25·0 months, respectively. Univariate analyses showed patients with one versus >one prior line of therapy had longer OS. Multivariate analyses identified that one prior line of therapy affected PFS; Eastern Cooperative Oncology Group (ECOG) performance status, simplified MCL international prognostic index (sMIPI) score, bulky disease, and blastoid histology affected OS and PFS. Patients with blastoid versus non-blastoid histology had similar time to best response, but lower ORR, DOR, PFS and OS. OS and PFS were longer in patients with better sMIPI, patients with ECOG performance status 0-1, non-bulky disease and non-blastoid histology. Additionally, the proportion of patients with poor prognostic factors increased with increasing lines of therapy. Together, results suggest that patient outcomes following treatment failure with ibrutinib are related to the natural biological evolution of the disease.

Characterization of atrial fibrillation adverse events reported in ibrutinib randomized controlled registration trials.

The first-in-class Bruton's tyrosine kinase inhibitor ibrutinib has proven clinical benefit in B-cell malignancies; however, atrial fibrillation (AF) has been reported in 6-16% of ibrutinib patients. We pooled data from 1505 chronic lymphocytic leukemia and mantle cell lymphoma patients enrolled in four large, randomized, controlled studies to characterize AF with ibrutinib and its management. AF incidence was 6.5% [95% Confidence Interval (CI): 4.8, 8.5] for ibrutinib at 16.6-months versus 1.6% (95%CI: 0.8, 2.8) for comparator and 10.4% (95%CI: 8.4, 12.9) at the 36-month follow up; estimated cumulative incidence: 13.8% (95%CI: 11.2, 16.8). Ibrutinib treatment, prior history of AF and age 65 years or over were independent risk factors for AF. Multiple AF events were more common with ibrutinib (44.9%; comparator, 16.7%) among patients with AF. Most (85.7%) patients with AF did not discontinue ibrutinib, and more than half received common anticoagulant/antiplatelet medications on study. Low-grade bleeds were more frequent with ibrutinib, but serious bleeds were uncommon (ibrutinib, 2.9%; comparator, 2.0%). Although the AF rate among older non-trial patients with comorbidities is likely underestimated by this dataset, these results suggest that AF among clinical trial patients is generally manageable without ibrutinib discontinuation (clinicaltrials.gov identifier: 01578707, 01722487, 01611090, 01646021).

Indirect Treatment Comparisons of Ibrutinib Versus Physician's Choice and Idelalisib Plus Ofatumumab in Patients With Previously Treated Chronic Lymphocytic Leukemia.

PURPOSE: Treatment options for patients with relapsed or refractory chronic lymphocytic leukemia (R/R CLL) are limited. Until recently, few effective treatment options existed, and even with the advent of new agents, studies evaluating comparative efficacy are scarce. In the Ibrutinib Versus Ofatumumab in Patients With Relapsed or Refractory Chronic Lymphocytic Leukemia (RESONATE) Phase III study, ibrutinib, an oral, once-a-day, first-in-class covalent Bruton tyrosine kinase inhibitor, improved progression-free survival (PFS) and overall survival (OS) compared with ofatumumab (PFS hazard ratio [HR] = 0.106 and OS HR = 0.369 [adjusted for crossover] at a median of 16 months' follow-up). We sought to establish the relative efficacy of ibrutinib versus other treatment options for patients with R/R CLL using indirect comparison methods. METHODS: A systematic literature review was conducted to identify clinical trials sharing a common treatment arm with the RESONATE Phase III trial such that a network meta-analysis or indirect treatment comparisons (ITCs) could be conducted. Two trials were identified, each using the same comparator (ofatumumab) as the RESONATE study. Two pairwise ITCs were conducted using the Bucher method to establish the relative treatment efficacy of ibrutinib versus (1) idelalisib plus ofatumumab in the first study and (2) physician's choice, defined as a mix of therapies commonly used in R/R CLL, in the second study. Odds ratios for these ITCs were calculated for overall response rate (ORR) and HRs for PFS and OS. FINDINGS: A strong and consistent trend of superiority for ibrutinib was observed via these ITC models with idelalisib plus ofatumumab and physician's choice for ORR, PFS, and OS. Ibrutinib revealed prolonged PFS and OS versus comparators (PFS HR = 0.06; 95% CI, 0.04-0.11; and OS HR = 0.25; 95% CI, 0.12-0.54), physician's choice (PFS HR = 0.41; 95% CI, 0.25-0.66; and OS HR = 0.50; 95% CI, 0.23-1.08), and idelalisib plus ofatumumab. These findings were robust and continued to favor ibrutinib when adjusting (where appropriate) for underlying differences in patient population between the trials. Some trial differences were not accounted for in the models and thus some limitations remain; however, consistency of results supports the overall findings. IMPLICATIONS: In a randomized Phase III study, ibrutinib significantly improved ORR, PFS, and OS in patients with R/R CLL versus ofatumumab. In ITC models that used ofatumumab as the common comparator, ibrutinib appears to have higher ORR and longer PFS and OS versus both idelalisib plus ofatumumab and physician's choice. In the absence of head-to-head studies and taking into consideration inherent limitations of ITCs, these models provide useful estimates of comparative efficacy.

Early response with dasatinib or imatinib in chronic myeloid leukemia: 3-year follow-up from a randomized phase 3 trial (DASISION).

This analysis explores the impact of early cytogenetic and molecular responses on the outcomes of patients with chronic myeloid leukemia in chronic phase (CML-CP) in the phase 3 DASatinib versus Imatinib Study In treatment-Naive CML patients trial with a minimum follow-up of 3 years. Patients with newly diagnosed CML-CP were randomized to receive 100 mg dasatinib (n = 259) or 400 mg imatinib (n = 260) once daily. The retrospective landmark analysis included patients evaluable at the relevant time point (3, 6, or 12 months). Median time to complete cytogenetic response was 3 vs 6 months with dasatinib vs imatinib. At 3 and 6 months, the proportion of patients with BCR-ABL transcript levels ≤10% was higher in the dasatinib arm. Deeper responses at 3, 6, and 12 months were observed in a higher proportion of patients on dasatinib therapy and were associated with better 3-year progression-free survival and overall survival in both arms. First-line dasatinib resulted in faster and deeper responses compared with imatinib. The achievement of an early molecular response was predictive of improved progression-free survival and overall survival, supporting new milestones for optimal response in patients with early CML-CP treated with tyrosine kinase inhibitors. This study was registered at www.clinicaltrials.gov as NCT00481247.

Cardiac safety of pegylated liposomal doxorubicin (Doxil/Caelyx) demonstrated by endomyocardial biopsy in patients with advanced malignancies.

Although conventional doxorubicin demonstrates broad activity, its clinical use is limited by cardiotoxicity. A more recent analysis suggests conventional doxorubicin-related cardiotoxicity occurs more frequently and at lower cumulative doses than previously reported. Pegylated liposomal doxorubicin, designed to maintain or improve conventional doxorubicin activity while reducing toxicities, has demonstrated improved cardiac safety versus conventional doxorubicin. In this prospective study, we evaluated endomyocardial biopsies to determine the cardiac effects of pegylated liposomal doxorubicin in patients with advanced malignancies receiving doxorubicin-equivalent doses > or = 550 mg/m2 (including pegylated liposomal doxorubicin) or > or = 400 mg/m2 pegylated liposomal doxorubicin alone. Eight patients were enrolled, and 10 biopsy scores were obtained (two patients had two biopsies). Median biopsy score (Billingham scale) was 0.75 (range, 0-1.5) after a median pegylated liposomal doxorubicin dose of 707.5 mg/m2 and median total anthracycline exposure of 908.5 mg/m2. These results suggest that pegylated liposomal doxorubicin minimizes doxorubicin-related cardiotoxicity, even at doses exceeding the recommended lifetime cumulative conventional dose (450-550 mg/m2).