Lilly ICOS LLC Friday won FDA approval for Cialis, an erectile dysfunction drug shown to improve activity up to 36 hours after dosing.
Cialis (tadalafil) is the third oral PDE5 inhibitor approved for ED since Viagra was launched by New York-based Pfizer Inc. in 1998. The other product is Levitra (vardenafil), made by Bayer AG, of Leverkusen, Germany, and GlaxoSmithKline plc, of London.
Cialis, which is expected to hit the market in December, has some unique qualities. Not only does it help improve sexual function over a longer period of time (Viagra works for about six hours), but some patients achieve erection 30 minutes after dosing. Also, Paul Clark, chairman and CEO of ICOS, said absorption of Cialis is not impacted by food, including high-fat meals. Lilly ICOS is a joint venture that was formed by ICOS, of Bothell, Washington, and Eli Lilly and Co., of Indianapolis, to develop Cialis.
As for approval of its first drug in the U.S., Clark was thrilled.
"For a company of our size, Cialis has the opportunity to be a real difference maker. Any large pharmaceutical company would love to be launching Cialis today, but it is ICOS and Lilly," Clark told BioWorld Today. "For us, after 12 years and a lot of work, it sure feels good to have our first U.S. approval. It's unusual for a biotech company to have a product on the market; if you take a look at the 1,200 or so biotechs across the U.S., for ICOS to get this, especially a potential blockbuster, is certainly very significant."
Indeed, Clark said approval of Cialis transforms ICOS from a research company to a fully integrated company.
"So the first chapter of our dream has now been realized," he said.
Lilly ICOS provides the companies a 50-50 split in North American and Europe. In other territories, including Australia, Asia, Africa and South America, Lilly has rights and is required to pay royalties to the joint venture.
Clark said Cialis has been on the market in Europe (50 countries in total) for about nine months, and in that time, the product has captured about 30 percent of the market. As of Sept. 30, Clark said sales had reached about $100 million and approximately 1 million men had been dosed. Meanwhile, Viagra brought in about $2 billion last year.
Cialis works by inhibiting PDE5, or phosphodiesterase type 5, an enzyme in smooth muscle that controls the level of cyclic GMP (guanylic acid). Inhibiting PDE5 increases the level of cyclic GMP, allowing blood vessels to dilate.
The safety and efficacy of Cialis was evaluated in 22 clinical trials in more than 4,000 patients. Cialis was shown to be effective in treating ED in patients 27 to 87 years old, including patients with other underlying medical conditions. In two of the trials, men had ED associated with diabetes or following radical prostatectomy for prostate cancer.
Clark said side effects associated with Cialis were mild to moderate, with the most common events being headache, upset stomach, muscle ache or back pain.
"These are fairly common among drugs in this class," he said. "The discontinuation rate due to side effects is pretty low and similar to placebo. One should not take nitrates if taking PDE5 inhibitors."
Lilly ICOS filed its new drug application for Cialis in mid-2001, but was stalled later when the FDA issued a letter saying the product would be approved contingent upon additional confirmatory clinical pharmacology studies, labeling negotiations and manufacturing inspections. (See BioWorld Today, June 29, 2001, and May 1, 2002.)
The companies submitted necessary supplemental data in July. (See BioWorld Today, July 3, 2003.)
In recent weeks, Lilly ICOS released Phase III data indicating that Cialis produced efficacy in men who've undergone surgery for prostate cancer. (See BioWorld Today, Oct. 13, 2002.)
ICOS' stock (NASDAQ:ICOS) fell $1.37 Friday to close at $43.66.