Connetics Commences Phase III Clinical Trial With Primolux for Atopic Dermatitis and Psoriasis; Second Drug Program to Include Connetics' Patented Emollient Foam Technology.

PALO ALTO, Calif. -- Connetics Corporation (Nasdaq:CNCT), a specialty pharmaceutical company that develops and commercializes dermatology products, today announced it has commenced the Phase III clinical program for Primolux(TM) (formerly referred to as OLUX-EF), a super high-potency topical steroid, formulated with 0.05% clobetasol propionate in the Company's proprietary VersaFoam-EF(TM) emulsion foam delivery vehicle. The clinical program will consist of two Phase III trials focusing on atopic dermatitis and psoriasis. Subject to successful Phase III trial outcomes, Connetics intends to submit a New Drug Application to the U.S. Food and Drug Administration by the end of 2005.

Primolux represents Connetics' second product entry into the super high-potency topical steroid market. The annual U.S. market opportunity for super high-potency topical steroids in all specialties is currently estimated to exceed $545 million. Primolux will be delivered in the VersaFoam-EF emulsion formulation, a completely different delivery vehicle than OLUX(R), which utilizes the hydro-ethanolic VersaFoam formulation. The VersaFoam-EF delivery vehicle will allow Primolux to compete in a new segment of the super high-potency topical steroid market.

VersaFoam-EF is an important advancement in topical steroid therapy. Connetics developed VersaFoam-EF as a cosmetically and functionally elegant and ethanol free formulation to compete with creams, emollients and ointment-based treatments. The company was issued a patent on this technology in May 2004. The annual U.S. market opportunity for topical steroids formulated in creams, emollients and ointment-based products in all specialties is estimated to exceed $700 million.

"The commencement of our second Phase III clinical program involving our patented emulsion foam delivery vehicle is an exciting opportunity for Connetics," said Lincoln Krochmal, M.D., Executive Vice President of Research and Product Development for Connetics. "With a VersaFoam-EF formulation of our low-potency steroid product Desilux and our super high-potency steroid Primolux now in clinical development, we are looking forward to offering dermatologists a complete line of topical steroids with enhanced cosmetic elegance and superior drug delivery."

"By incorporating a strong moisturizing benefit with a super high-potency steroid like clobetasol into our proprietary VersaFoam delivery vehicle, we will provide patients with a novel product formulation which we believe will lead to greater patient compliance and increased patient satisfaction and benefit," said Krochmal.

About Connetics

Connetics Corporation is a specialty pharmaceutical company focused on the development and commercialization of innovative therapeutics for the dermatology market. Connetics has branded its proprietary foam drug delivery vehicle VersaFoam(R). The Company's marketed products are OLUX(R) (clobetasol propionate) Foam, 0.05%, Luxiq(R) (betamethasone valerate) Foam, 0.12%, Soriatane(R) (acitretin) capsules and Evoclin(TM) (clindamycin) Foam, 1%. Connetics is developing Velac(R) (a combination of 1% clindamycin and 0.025% tretinoin) Gel, for treating acne, Desilux(TM) (desonide) VersaFoam-EF, 0.05% a low-potency topical steroid formulated to treat atopic dermatitis, and Primolux(TM) (clobetasol propionate) VersaFoam-EF, 0.05%, a super high-potency topical steroid formulated to treat atopic dermatitis and plaque psoriasis. Connetics' product formulations aim to improve the management of dermatological diseases and provide significant product differentiation. Connetics' proprietary formulations have earned wide acceptance by both physicians and patients due to their clinical effectiveness, high quality and cosmetic elegance. For more information about Connetics and its products, please visit www.connetics.com.

Forward-Looking Statements

This press release contains "forward-looking statements" within the meaning of the Securities Litigation Reform Act. These statements include those regarding patient satisfaction and benefit from Primolux along with the projected outcome of the Phase III clinical program and the planned filing of a New Drug Application for Primolux. These statements are based on certain assumptions made by Connetics' management based on its experience with the Primolux development process along with its analysis of historical business trends, current market conditions, expected future developments with Primolux and its market and other factors it believes are appropriate in the circumstances. These statements are also subject to a number of risks and uncertainties, many of which are beyond Connetics' control, and which could cause actual events to differ materially from those expressed in the forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, risks and other factors that are discussed in documents filed by Connetics with the Securities and Exchange Commission from time to time, including Connetics' Annual Report on form 10-K filed for the year ended December 31, 2004. Forward-looking statements represent the judgment of the Company's management as of the date of this release, and Connetics disclaims any intent or obligation to update any forward-looking statements.