Sprout Pharmaceuticals has moved a step closer to securing approval for a drug to treat reduced libido in women after getting a green light from an FDA advisory committee.
The panel voted by 18 to 6 that the drug – called flibanserin – should be approved to treat hypoactive sexual desire disorder (HSDD) in pre-menopausal women, opening the door for a possible FDA approval by August 18.
However, the committee said that given the intended use of the drug for sexual dysfunction in otherwise healthy women Sprout will need to draw up a comprehensive risk-management plan for delivering the therapy, and this will have to extend beyond the labelling for the product.
While the vote was positive, it could have been closer as a number of panellists indicated they were voting in favour with some reservations about flibanserin, which acts as an agonist of serotonin 5-HT1A receptors and an antagonist of 5-HT2A receptors.
There have been some instances of low blood pressure and fainting in patients taking the drug in trials, which can be exacerbated by alcohol or other medications such as fluconazole, a commonly used antifungal.
Overall, the advisory committee seemed in favour of the implementation of a Risk Evaluation and Mitigation Strategy (REMS) for flibanserin, a commonly used protocol for drugs with safety concerns, which could include patient communication plans, medication guides and potentially even measures to help ensure safe use such as prescriber certification.
REMS are already in place for other ‘lifestyle’ drugs such as Vivus’ Qsymia (phentermine/topiramate) for obesity and Pfizer’s smoking cessation therapy Chantix (varenicline).
If the FDA clears flibanserin it will mark the end of a long road for Sprout, which has previously been turned down by the FDA in 2010 and 2014 on the grounds that the company had not provided enough evidence of its efficacy and safety. It resubmitted the application in February.
Flibanserin was originally developed by Boehringer Ingelheim, but was shelved by the German drugmaker after it became apparent that the FDA had reservations about the drug. Sprout acquired rights to the programme in 2011 and says it hopes to market it under the Addyi trade name.
If given the nod by the FDA, flibanserin would become the first ever drug approved for HSDD, although other companies are working in this area. Palatin Technologies has a candidate called bremelanotide in late-stage testing, while S1 Biopharma should report results from a phase IIb trial of Lorexys (bupropion and trazodone) in HSDD in the coming weeks.