Advisors to the US Food and Drug Administration has recommended approval for GlaxoSmithKline's Votrient for sarcoma but has voted against Taltorvic, a similar treatment from Merck & Co and Ariad Pharmaceuticals.
First up, the agency's Oncologic Drugs Advisory Committee voted 11 to 2 that evidence from clinical studies support a favourable risk-benefit for use of Votrient (pazopanib) in treating patients with advanced soft tissue sarcoma who have received prior chemotherapy. Data from one of those trials, a 369-patient study, showed that Votrient enabled patients to live a median of 4.6 months, some 3.1 months longer than placebo, without their disease progressing. However, that trial excluded patients with gastrointestinal stromal tumours and adipocytic sarcomas.
Panellists were concerned about the side effects profile of the drug, given that 98 of the 296 patients on Votrient experienced a serious adverse event compared with 29 on placebo; 47 patients on the GSK therapy discontinued the treatment due to adverse events, compared with six on placebo.
Rafael Amado, head of GSK Oncology, noted that treatment options for patients with advanced soft tissue sarcoma are limited, so "we are therefore pleased that the Committee took a favourable view". Votrient is already approved in the USA and Europe for the treatment of advanced renal cell carcinoma.
However, the ODAC voted 13-1 against the use of Merck and Ariad's Taltorvic (ridaforolimus) as maintenance therapy for patients with metastatic soft-tissue sarcoma or bone sarcoma whose disease has not progressed after at least four cycles of chemotherapy.
Merck and Ariad had presented data which showed that patients on Taltorvic had a median progression-free survival of 17.7 weeks compared with 14.6 weeks for those on placebo. However the panel believes that no significant difference was observed between the groups in terms of overall survival and although patients did experience a longer disease-free period before their cancer returned when receiving Taltorvic, an oral mTOR inhibitor, the delay was not significant. They were also concerned about side effects, with 60% of patients experiencing a serious drug-related issue.
Despite the nature of the vote against, Merck's vice president for oncology clinical research Eric Rubin said the company "remains confident in the potential" of the drug "for an indication where patients have limited options". He added that the firm "“remains committed to bringing forward this promising therapy for patients with metastatic sarcoma, and look forward to further discussions with the FDA regarding this application".