Serono, Europe's biggest biotechnology group, increased first quarter net profit by 37 per cent to $72 million (SFr124.5 million) as sales grew and gross margins continued to improve.

The increase in business at the Geneva-based company was in line with analysts' expectations.

Serono, which makes the multiple sclerosis drug, Rebif, and hormone treatments for infertility and AIDS-related weight loss, did not update its profit forecast for the remainder of 2001.

The company revealed in March that it expected strong growth to continue this year, with net income expected to come in 20 per cent higher over the year while sales should increase between 15 and 20 per cent. In 2000 sales at Serono increased 15 per cent over the year.

"Our strong start to 2001 has been driven by the rapidly growing sales of Rebif," chief executive Ernesto Bertarelli said in a statement.

Rebif sales increased by 71 per cent to $83 million as its non-US market share widened to 31 per cent.

Bertarelli said that eagerly awaited results of Rebif's head-to-head trials versus Biogen's rival Avonex drug would be announced on May 8.

Sales of its Gonal-F fertility drug rose by 15 per cent to $101 million while a new needle-free delivery system helped the turnover of the growth hormone, Saizen, rise 18.3 per cent to $22.7 million.

Sales of the AIDS-wasting drug, Serostim, slipped to $29.5 million from $33.3 million. Serono said reimbursement issues in some US states had been resolved and that the number of Serostim prescribers was growing in an evolving market.

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