Genentech/Xoma Raptiva Promotions Likely To Focus On Dosing Convenience

Genentech/Xoma plan to differentiate the psoriasis agent Raptiva from other biologics by highlighting Raptiva's dosing convenience.

"Our convenience really is a winning third component necessary for this market...particularly because this is a market that involves younger people who are active in the marketplace and earning a living," Xoma Chief Medical and Scientific Officer Patrick Scannon, MD, PhD, told investors on an Aug. 13 conference call.

On the first two components - safety and efficacy - "I think we compare favorably with any product or product candidate that we're aware of," he said.

Once Raptiva (efalizumab) is approved, Genentech will be responsible for developing its marketing campaign. The companies co-developed the biologic; under the terms of the deal, Xoma provided 25% of the Phase III costs and will record 25% of the revenue.

Genentech will likely emphasize the convenience of Raptiva's once-weekly subcutaneous injection formulation. Biogen's Amevive , which is currently the only biologic approved for the treatment of psoriasis, is administered once weekly as an intravenous or intramuscular injection. Amevive (alefacept) was approved Jan. 30 (¹ (Also see "Biogen Amevive Marketing Focus Will Be Duration Of Antipsoriatic Response" - Pink Sheet, 3 Feb, 2003.), p. 3).

Xoma expects to launch Raptiva by the end of the year. "We're looking forward to a potential product launch by year-end 2003, plus continued clinical development in additional indications," CEO John Castello said.

The companies filed the Raptiva BLA on Dec. 23, 2002, making the expected user fee date Oct. 23. FDA's Dermatologic & Ophthalmic Drugs Advisory Committee will review the targeted T-cell modulator on Sept. 9 for the treatment of moderate-to-severe plaque psoriasis in adults (² 'The Pink Sheet' Aug. 4, 2003, In Brief).

The psoriasis market could see a third entrant during the first half of 2004. Amgen submitted an sBLA for its rheumatoid arthritis therapy Enbrel for the treatment of moderate-to-severe plaque psoriasis June 30 (³ 'The Pink Sheet' July 14, 2003, In Brief).

Enbrel (etanercept) is the first tumor necrosis factor inhibitor to be filed for the treatment of psoriasis; Centocor's Remicade (infliximab) is in Phase III trials for the indication and Abbott's Humira (adalimumab) is in Phase II.

Raptiva clinical investigators presented long-term data from efalizumab trials at the American Association of Dermatologists annual meeting in July.

In a 24-week open-label Phase III study, 44% (161/368) of patients treated continuously with 1 mg/kg of Raptiva achieved a Psoriasis Area and Severity Index (PASI) score of 75, or 75% improvement from baseline.

Results from a separate 21-month, open-label trial evaluating the long-term safety of continuous treatment with Raptiva showed that 67% (130/194) of patients achieved a PASI score of 75 and 34% (66/194) achieved PASI 90.

Genentech/Xoma have completed enrollment for a Phase II trial evaluating Raptiva in active and progressive psoriatic arthritis. In the multi-center study, patients receive standard therapy plus weekly Raptiva injections or placebo. The primary endpoint is the reduction in signs and symptoms of the disease measured by the ACR 20 score.

If approved, Raptiva is expected to enter a crowded psoriatic arthritis market. Enbrel was approved for the indication on Jan. 15, 2002; Remicade and Humira are in Phase III studies.

Raptiva was being studied for the treatment of moderate-to-severe rheumatoid arthritis, but Genentech and Xoma discontinued development after a Phase II trial failed to show an overall net benefit (⁴ 'The Pink Sheet' May 19, 2003, In Brief).

Xoma is looking for development partners for two pipeline products: ING-1, an anti-cancer monoclonal antibody in Phase I, and Neuprex (opebacan). The company licensed Neuprex rights to Baxter in January 2000; Baxter returned all rights in July.

Other products in Xoma's pipeline include MLN2201 (Phase I), a monoclonal antibody under development for conditions related to inflammation of the heart and blood vessels as part of a collaboration with Millennium, and XMP629 (preclinical), a topical antibacterial compound for the treatment of acne.