Researchers are also testing a number of other solutions that may help relieve the symptoms of interstitial cystitis, including hyaluronan, chondroitin sulfate and oxybutynin.

CNN: Interstitial cystitis

Its products--including Synvisc, which is injected into the knee to treat osteoarthritis, and Hylaform, which corrects facial wrinkles--are all based on a single chemical called hyaluronan.

FORBES: Biotech Briefing: Genzyme Buys Biomatrix

Although Biomatrix has been successful in marketing hyaluronan so far, it has had some problems, including buzz that got so negative it sued to stop unflattering comments posted on Web message boards.

FORBES: Biotech Briefing: Genzyme Buys Biomatrix