In this edition of “How I will treat my next patient,” I highlight two recent presentations regarding potential improvements in the convenience and tolerability of treatment for two hematologic malignancies: multiple myeloma and chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL).
SC-Dara in myeloma
At the 2019 annual meeting of the American Society of Clinical Oncology,, and colleagues, reported the results of , a phase 3 evaluation in 522 patients with multiple myeloma who were randomized to subcutaneous daratumumab (SC-Dara) or standard intravenous infusions of daratumumab (IV-Dara). A previous phase 1b study ( ) had suggested comparable efficacy from the more convenient SC regime. Whereas conventional infusions of IV-Dara (16 mg/kg) take several hours, the SC formulation (1,800 mg–flat dose) is delivered in minutes. In COLUMBA, patients were randomized between SC- and IV-Dara weekly (cycles 1-2), then every 2 weeks (cycles 3-6), then every 4 weeks until disease progression.
Among the IV-Dara patients, the median duration of the first infusion was 421 minutes in cycle 1, 255 minutes in cycle 2, and 205 minutes in subsequent cycles – compatible with standard practice in the United States. As reported, at a median follow-up of 7.46 months, the efficacy (overall response rate, complete response rate, stringent-complete response rate, very good-partial response rate, progression-free survival, and 6-month overall survival) and safety profile were non-inferior for SC-Dara. SC-Dara patients also reported higher satisfaction with therapy.
What this means in practice
It is always a good idea to await publication of the manuscript because there may be study details and statistical nuances that make SC-Dara appear better than it will prove to be. For example, patient characteristics were slightly different between the two arms. Peer review of the final manuscript could be important in placing these results in context.
However, for treatments that demand frequent office visits over many months, reducing treatment burden for patients has value. Based on COLUMBA, it appears likely that SC-Dara will be a major convenience for patients, without obvious drawbacks in efficacy or toxicity. Meanwhile, flat dosing will be a time-saver for physicians, nursing, and pharmacy staff. If the price of the SC formulation is not exorbitant, I would expect a “win-win” that will support converting from IV- to SC-Dara as standard practice.
Acalabrutinib in CLL/SLL
Preclinical studies have shown acalabrutinib (Acala) to be more selective for Bruton’s tyrosine kinase (BTK) than the first-in-class agent ibrutinib, with less off-target kinase inhibition. As reported at the 2019 annual congress of the European Hematology Association by, and colleagues in the phase 3 , 310 patients with previously treated CLL were randomized between oral Acala twice daily and treatment of physician’s choice (TPC) – either idelalisib plus rituximab (maximum of seven infusions) or bendamustine plus rituximab (maximum of six cycles).
Progression-free survival was the primary endpoint. At a median of 16.1 months, progression-free survival had not been reached for Acala, in comparison with 16.5 months for TPC. Significant benefit of Acala was observed in all prognostic subsets.
Although there was no difference in overall survival at a median follow-up of about 16 months, 85% of Acala patients had a response lasting at least 12 months, compared with 60% of TPC patients. Adverse events of any grade occurred in 94% of patients treated with Acala, with 45% being grade 3-4 toxicities and six treatment-related deaths.