BioSante plans new trials despite LibiGel's failure to perform
This article was originally published in Scrip
BioSante Pharmaceuticals is pursuing development of its female sexual dysfunction drug LibiGel (testosterone gel) despite the product failing to show it was any better than placebo in treating hypoactive sexual desire disorder in postmenopausal women in two Phase III trials, BLOOM1 and BLOOM2, last year.
When news of the LibiGel's Phase III failure broke last December, the company's stock lost more than three-quarters of its value (scipintelligence.com, 16 December 2011).
It recovered slightly when BioSante secured FDA approval of Bio-T-Gel, another testosterone gel product that the firm has licensed to Teva's US unit as a treatment for male hypogonadism, or low levels of testosterone (scripintelligence.com, 16 February 2012).
The company plans to initiate two new LibiGel Phase III efficacy trials. "This decision is based on an extensive analysis of previous efficacy data, consultation with key opinion leaders in female sexual dysfunction, testosterone therapy and placebo effects, as well as a meeting with the US FDA," the company said.
The news was not greeted all that well by investors, with BioSante's stock closing almost 8% down at $2.36 on the news (11 June).
BioSante also intends to continue the on-going LibiGel Phase III cardiovascular and breast cancer safety study as per protocol. "The study represents the largest data base of the safety of testosterone in women," the company noted. The primary analysis of the safety study is slated for the second half of 2012.
The protocol for the two new efficacy trials is still being designed. BioSante said it intends to apply for an FDA special protocol assessment (SPA) agreement prior to starting the new studies. The previous trials were also conducted under a SPA. "Currently, it is expected that the efficacy trials will include the same FDA-required efficacy endpoints as prior Phase III efficacy trials: an increase in the number of satisfying sexual events and sexual desire, and decreased distress associated with low desire."
In the two completed Phase III efficacy trials, LibiGel performed "as predicted based on previous experience with testosterone products", said the company. However, the placebo response in the two efficacy trials was "greater than expected". Therefore, LibiGel was not shown to be statistically different from placebo, explained BioSante.
BioSante also has a series of cancer vaccines in early stage clinical development (scripintelligence.com, 28 February 2012).