Schering AG of Germany – now controlled by majority shareholder Bayer - said yesterday it had been granted approval in the USA to market its multiple sclerosis drug Betaseron for patients in the early stages of the disease.

Betaseron (interferon beta-1b), sold by Schering’s Berlex subsidiary in the USA, is the company’s biggest-selling product but has been facing increasing competition of late from other MS products, including rival interferons from Biogen Idec and Serono and Teva’s Copaxone (glatiramer acetate).

Approval in early MS could be critical for Betaferon, as it could mean that it captures patients newly-diagnosed with the disease before its rivals, and so stand a greater chance that Betaferon will be used as their symptoms progress.

According to the new labelling, early stage MS patients are defined as those who have experienced one first attack and have a magnetic resonance imaging (MRI) scan that shows features consistent with MS. Approval of this use in Europe was granted in June.

The approval was based on the results of the BENEFIT trial, which showed that giving Betaferon in the early stages of the disease reduced the risk of developing full-blown MS by 50% compared to placebo.