Acalabrutinib, given alone or in combination with obinutuzumab, showed favorable progression-free survival (PFS) and overall survival (OS), compared with other frontline therapies for chronic lymphocytic leukemia (CLL) in fludarabine-ineligible patients, according to the results of a meta-analysis comparing clinical trial results.
Researchers conducted a systematic literature review for applicable CLL studies that examined frontline treatments in order to compare the results with data on acalabrutinib (monotherapy and in combination with obinutuzumab) from patients in the ELEVATE-TN study (), according to a report published in .
Matthew S. Davids, MD, MMSc, of the Dana-Farber Cancer Institute in Boston, and colleagues performed a network meta-analysis (NMA) comparing acalabrutinib versus other standard frontline therapies for CLL in patients for whom fludarabine-based treatment is not appropriate.
“In the absence of head-to-head trial data, NMAs allow for simultaneous comparisons of a number of interventions with multiple comparators, by synthesizing direct and indirect evidence,” the authors stated.
Eight randomized controlled trials (RCTs) met the criteria for comparison.
The researchers constructed two evidence networks: Network A comprised solely RCTs that met the inclusion criteria, and Network B comprised seven RCTs and a published cross-trial comparison of ibrutinib from RESONATE-2 and chlorambucil plus obinutuzumab from iLLUMINATE. PFS and OS results were reported by using hazard ratios and 95% credible intervals.
Both networks showed a significant improvement in PFS for acalabrutinib plus obinutuzumab over all comparators, according to the researchers. Both networks also showed a significant improvement in PFS for acalabrutinib monotherapy versus most comparators, with a significant difference to ibrutinib monotherapy found in Network A but not Network B.
Conversely, a significant difference in PFS was observed for acalabrutinib monotherapy versus venetoclax plus obinutuzumab in Network B but not Network A.
Overall survival hazard ratios ranged from 0.18 to 0.65 in favor of acalabrutinib-based treatment, but not all were significant. Acalabrutinib plus obinutuzumab ranked highest in terms of PFS and OS improvement, followed by acalabrutinib monotherapy.
“Although our NMAs provide useful insights into the relative efficacy of acalabrutinib, compared with other frontline treatments of CLL, the results cannot be considered confirmatory, and head-to-head randomized trials are needed, especially to compare the efficacy of acalabrutinib versus other targeted agents,” the researchers concluded.
AstraZeneca sponsored the study. The authors reported funding from AstraZeneca and numerous other pharmaceutical companies.
SOURCE: Davids MS et al. Clin Ther. 2020 Oct 5. doi: 10.1016/j.clinthera.2020.08.017.