Matching-adjusted indirect comparison of Acalabrutinib versus Ibrutinib in relapsed/refractory mantle cell lymphoma.

OBJECTIVE: In the absence of head-to-head clinical trials, matching-adjusted indirect comparison (MAIC) was used to compare 2 Bruton tyrosine kinase inhibitors (BTKis) approved for the treatment of relapsed/refractory (R/R) mantle cell lymphoma (MCL). This analysis compares the efficacy and safety of acalabrutinib versus ibrutinib using a more mature dataset than a previously published MAIC. METHODS: Individual patient data from 122 patients treated with acalabrutinib in a phase 2 study were weighted to match aggregate baseline characteristics of patients pooled from 3 separate trials of ibrutinib. Patients were matched on Eastern Cooperative Oncology Group performance status, simplified Mantle Cell Lymphoma International Prognostic Index, lactate dehydrogenase, prior lines of therapy, tumor burden, and blastoid histology. Outcomes assessed included progression-free survival (PFS), overall survival (OS), and adverse events. RESULTS: After matching, differences in PFS between acalabrutinib (median 17.8 months) and ibrutinib (median 12.8 months) were not statistically significant (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.74-1.15; P = 0.48). Similarly, after matching, OS differences between acalabrutinib (median 36.5 months) and ibrutinib (median 27.9 months) did not reach statistical significance (HR, 0.87; 95% CI, 0.64-1.17; P = 0.35). Acalabrutinib was associated with an improved safety profile compared with ibrutinib, with statistically significantly lower rates of grade ≥3 atrial fibrillation and thrombocytopenia. CONCLUSIONS: This comparison of 2 BTKis used in the treatment of R/R MCL showed that PFS and OS risk was not statistically different between the treatments; however, acalabrutinib had an improved safety profile compared with ibrutinib.

Mantle cell lymphoma (MCL) is an aggressive and rare type of cancer that affects lymphoid cells and often returns after previously responding to treatment (relapsed) or stops responding to treatment (refractory). Acalabrutinib and ibrutinib belong to a class of drugs referred to as Bruton tyrosine kinase inhibitors and are approved for the treatment of relapsed or refractory MCL. There is currently no direct head-to-head trial available to compare the efficacy and safety of acalabrutinib and ibrutinib in patients with relapsed or refractory MCL. To compare these drugs, the authors used a method referred to as a matching-adjusted indirect comparison (MAIC), which allows for comparison of the efficacy and safety of acalabrutinib versus ibrutinib using data from different clinical trials. This MAIC study found that there were no statistically significant differences in survival outcomes in patients with relapsed or refractory MCL who were treated with either acalabrutinib or ibrutinib. However, acalabrutinib was associated with an improved safety profile compared with ibrutinib. When there are many treatment options available for patients, knowing how different treatments compare in terms of efficacy and safety may help patients and physicians choose the most appropriate therapy. Although direct comparisons are the most accurate way to compare different treatments, when they are unavailable, MAIC studies can help patients and healthcare providers in the decision-making process.

Primary results of STRONG: An open-label, multicenter, phase 3b study of fixed-dose durvalumab monotherapy in previously treated patients with urinary tract carcinoma.

BACKGROUND: Prior durvalumab (anti-PD-L1 agent) studies in platinum-refractory metastatic urothelial carcinoma evaluated a dose of 10 mg/kg administered every two weeks. The nonrandomised phase 3b STRONG study (NCT03084471) evaluated the safety and efficacy of fixed-dose durvalumab at a more convenient dosing schedule in a previously treated patient population, more similar to a real-world clinical setting. PATIENTS AND METHODS: 867 patients with urothelial or nonurothelial urinary tract carcinoma (UTC) who progressed on or after platinum or nonplatinum chemotherapy were treated with durvalumab 1500 mg every four weeks; 87% had an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0-1, and 13% had an ECOG PS of 2. The primary end-point was the incidence of adverse events of special interest (AESIs), including immune-mediated AEs (imAEs). Secondary and exploratory end-points included overall survival (OS), objective response rate (ORR) and disease control rate (at six and 12 months) (DCR). RESULTS: AESIs of any grade were reported in 51% of patients (8% grade ≥ 3). The incidence of imAEs was 11% (2% grade ≥ 3). The median OS was 7.0 months (95% confidence interval [CI]: 6.4-8.2) and ORR was 18% (95% CI: 14.8-20.6), with complete responses in 5% of patients and a DCR at six months of 19% (95% CI: 16.1-22.1). CONCLUSION: Fixed-dose durvalumab monotherapy every four weeks has an acceptable safety profile and yields durable clinical activity in previously chemotherapy-treated patients with UTC. Safety and efficacy are consistent with previous durvalumab studies and other anti-PD-1/PD-L1 agents in this setting. CLINICALTRIALS. GOV IDENTIFIER: NCT03084471https://clinicaltrials.gov/ct2/show/NCT03084471.

Clinical evidence for the first-line treatment of advanced urothelial carcinoma: Current paradigms and emerging treatment options.

BACKGROUND: Patients with advanced urothelial carcinoma (UC) have poor outcomes, with 5-year survival rates of <5% for those with metastatic, stage IV disease. We have reviewed current treatment paradigms and emerging treatment options for these patients. METHODS: The websites of seven national or international organizations were searched for metastatic UC treatment guidelines. Systematic literature reviews were conducted to identify evidence from randomized controlled trials (RCTs) of chemotherapy for patients with previously untreated, unresectable, stage IV UC. Searches included congress databases and articles published between 1990 and 2018. In order to align with the latest treatment paradigms in first-line advanced UC, a focused literature search was conducted to identify evidence supporting immuno-oncology (IO) agents. RESULTS: For advanced UC, guidelines universally recommend cisplatin-based chemotherapy as first-line treatment for eligible patients and carboplatin-based regimens for those unfit to receive cisplatin. Despite the evaluation of a number of different cytotoxic regimens over the years, including triplet combinations, survival outcomes have not improved markedly with chemotherapy. Median overall survival with standard of care chemotherapy is ~13 months. Based on the results of single-arm, phase II studies, recent treatment guidelines have included atezolizumab (anti-PD-L1) and pembrolizumab (anti-PD-1) as first-line options for cisplatin-ineligible patients whose tumors express high levels of PD-L1. However, emerging evidence from RCTs of IO agents, including both cisplatin-eligible and cisplatin-ineligible patients, suggest that survival times exceeding 20 months are possible. CONCLUSIONS: After having reached a plateau with chemotherapy, the treatment landscape for advanced UC is evolving. Survival outcomes for patients with advanced UC are improving with treatment modalities involving IO agents.