Sprout Pharmaceuticals, Inc. has announced that the FDA has approved Addyi™, a drug for the treatment of acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. Addyi is the only FDA-approved drug for a condition that affects 10% of women in the US.
HSDD or inhibited sexual desire (ISD) is a sexual dysfunction characterized by a lack or absence of sexual fantasies and desire for sexual activity. To be considered a disorder, it must cause distress or interpersonal difficulties and not be better accounted for by a drug or other medical condition. A person with HSDD will not start or respond to a partner’s desire for sexual activity. Acquired HSDD refers to HSDD that appears in a person who did not have previous sexual desire problems.
Sprout Pharmaceuticals, based in Raleigh, N.C. “sprouted” out of Slate Pharmaceuticals in 2011. The company is focused solely on developing drugs for women with Hypoactive Sexual Desire Disorder (HSDD).
Addyi (flibanserin 100 mg) has been tested in a clinical trial of 8.500 premenopausal women with HSDD. The company reports that clinical trials were successful. Addyi increased desire for sex, reducing distress from the loss of sexual desire and increasing the number of satisfying sexual events. Women receiving flibanserin reported having an increase of “satisfying sexual events” (from 2.8 to 4.5 times a month). But women receiving placebo reported also an increase (from 2.7 to 3.7 times a month). Common side effects were dizziness, somnolence, nausea, fatigue, insomnia and dry mouth.
Mechanism of action
Sexual excitatory activity is driven by dopamine and norepinephrine, while the inhibitory activity is driven by serotonin. Flibanserin, a 5-HT1A receptor agonist, D4 receptor very weak partial agonist/antagonist, and 5-HT2A receptor antagonist, modulates neurotransmitters levels in specific brain areas, improving the balance between these inhibitory and excitatory effects.
Successful lobbying campaign
The FDA approval of Addyi represents a victory for a coalition called Even the Score that accused the FDA of gender bias for ignoring the sexual needs of women. The coalition claimed that there where several options for men to improve their sex lives, but none for women. However, this is the first and only drug that addresses a problem of libido. Critics claim the coalition pressed the FDA to approve a drug that is only marginally effective and has multiple side effects.