It slipped 40p to 622p amid continued nervousness about the prospects for Zantac, Glaxo's best selling anti-ulcer drug, which faces a new patent challenge in the US as well as the prospect of generic competition with the ending of the American patent on Tagamet, a competing product.
The Wellcome agreement involves Glaxo's 3TC compound, now in the late stages of development. The compound, generically known as lamivudine, is intended to work in combination with other HIV treatments such as Wellcome's Retrovir. Many scientists believe combination treatments rather than a single 'magic bullet' offer the best prospect for treating HIV. The companies hope to file for regulatory approval for the drug towards the end of the year.
Under the terms of the agreement Wellcome has been granted an option to develop and market 3TC for HIV, which if exercised would involve royalty payments to Glaxo based on sales.
Glaxo will, however, continue development of the drug for the treatment of hepatitis B.
Meanwhile, the Swedish drug company Astra has gained a licence to sell Losec, a major competitor to Zantac in Europe, in combination with an antibiotic, amoxycillin, for treating ulcers associated with H Pylori bacteria.
The treatement of ulcers with antibiotics is expected to whittle away at the market for Zanatc over the next few years.
gfblobWellcome shares dropped 22p on rumours that US sales of its key drug Zovirax had dropped from 20 to 8 per cent and worries about the routine vetting by the European Commission of its plans to link up with Warner-Lambert to market consumer health products.Reuse content