Prospects for an orally-active treatment for patients with multiple sclerosis diminished yesterday after Teva and partner Lundbeck shelved plans for a coated tablet formulation of Copaxone.

Copaxone (glatiramer acetate), already a billion dollar seller as an injectable, had reached the Phase II clinical testing stage in oral form, but results were disappointing, according to Teva. However, the Israeli firm said in a Securities and Exchange Commission filing that it was "considering future development of Copaxone in various non-parenteral formulations and will make a decision in the context of its entire MS portfolio,” implying that it might develop another oral form of the drug.

That decision will likely rest on the fortunes of laquinimod, another oral drug for MS that Teva licenses from Sweden’s Active Biotech. This drug is already in Phase II testing and has shown more promise clinically than oral Copaxone, according to analysts. Additional data from the laquinimid clinical programme is due later this year.

Teva said it had been developing oral Copaxone for six years, but that two rounds of Phase II trials had failed to show an acceptable level of efficacy for the drug in MS.

The first company to bring an oral MS drug to market is almost certain to have a billion dollar-plus product on its hands, according to Datamonitor, which has predicted that oral products will lead to a doubling of the market for MS treatments reaching $6 billion a year in 2012.

Other companies developing oral drugs for MS include Novartis with FTY720, just starting a Phase III trials programme, and Serono with its Mylinax (cladribine) candidate, also in Phase III trials. Teva has a passive interest in the latter drug, inherited through its merger with US firm Ivax. Meanwhile, Sanofi-Aventis has teriflunomide in late-stage testing, while GlaxoSmithKline and Tanabe are developing 683699 and Biogen Idec has BG-12, both in Phase II.