Novel Antibody-Drug Conjugate in Platinum-Resistant Ovarian Cancer
Posted: Tuesday, July 31, 2018
Lifastuzumab vedotin (LIFA), an anti–NaPi2b monoclonal antibody conjugated to monomethyl auristatin E, appeared to be well tolerated and displayed a small, albeit nonstatistically significant, improvement in progression-survival compared with the standard-of-care pegylated liposomal doxorubicin (PLD) in patients with platinum-resistant ovarian cancer. Published in the Annals of Oncology, this is reportedly the first randomized phase II trial to evaluate an antibody-drug conjugate in this patient population.
“This study highlights that [objective response rate] alone may not translate to durable responses with [antibody-drug conjugates], and that careful target selection, evaluation of target expression thresholds, response rate, and duration of response may all be important to the future development of antibody-directed cytotoxics in [ovarian cancer],” concluded Susana Banerjee, PhD, of the Royal Marsden National Health Service Foundation Trust, London, and colleagues.
In the study, 95 patients with platinum-resistant ovarian cancer were randomized to receive LIFA (n = 47) or PLD. The median progression-free survival in the LIFA group was 5.3 months versus 3.1 months with PLD in the intent-to-treat population; in patients with NaPi2b-high disease, the median progression-free survival was 5.3 months with LIFA versus 3.4 months with PLD. The objective response rate in those treated with LIFA was 34%, compared with 15% with PLD in the intent-to-treat population, and 36% and 14%, respectively, in those with NaPi2b-high disease.
As for toxicity, the rate of grade ≥ 3 adverse events was 46% with LIFA compared with 51% with PLD. Serious adverse events were reported in 30% of both treatment arms. The most common side effects reported in those who received LIFA were nausea, abdominal pain, and fatigue, compared with fatigue, nausea, and constipation in those who received PLD.