TAP withdraws NDA for impotence drug Uprima, resubmission "at later date"

TAP Pharmaceuticals, the joint venture established by Takeda ChemicalIndustries and Abbott Laboratories, has withdrawn its New Drug Application for the erectile dysfunction drug Uprima (apomorphine HCl tablets), a dopamine agonist which has been used for many years in the treatment of Parkinson's disease.

In a statement, TAP said that it is withdrawing the NDA "because it has additional data and ongoing studies that could further establish the drug's safety and efficacy profile." The firm added that "it is our hope that by taking the extra time to submit additional data, TAP will be able to provide a treatment with an even stronger product profile for men with ED."

The withdrawal could prove somewhat of a setback for TAP, which is believed to be the closest to market among the battery of ED therapies in development and a possible competitor to Pfizer's blockbuster oral impotence compound Viagra (sildenafil), which generated revenues in 1999 of more than $1 billion. Earlier this year, an FDA advisory panel backed the use of Uprima but voiced some concerns over serious side effects associated with the drug's use (Marketletter April 17). These included hypotension, syncope (temporary loss of consciousness) and bradycardia. The drug is also linked to other events such as nausea, dizziness, sweating and somnolence, and appears to interact with both alcohol and (like Viagra) nitrates.