US regulatory approvals for new biopharmaceuticals nearly doubled in the last decade compared to the 1990s, but developers face substantial challenges if they are to maintain that pace, according to a new report.

65 biopharmaceutical products received marketing approval from the US Food and Drug Administration (FDA) during 2000-2009, compared to 39 in the previous decade and just 13 in the 1980, says the study, which is published by the Tufts Center for the Study of Drug Development (CSDD).

"While the strong growth in approvals is positive news for biotech companies and patients alike, biopharmaceutical development remains complex and developers face substantial challenges if they are to continue winning approvals at the pace of the last decade," cautions study author Janice Reichert, a research assistant professor at Tufts University.

For example, she points out that average combined clinical and approval phase times for biopharmaceuticals rose to 95 months during the 2000s, up from 77 months in the 1990s.

"Moving forward, developers will be under pressure to further streamline the development process to assure greater consistency across compounds and within disease areas," Prof Reichert forecasts.

Her study also reports that: - as a percentage of all new biopharmaceuticals approved by the FDA, recombinant protein products increased slightly, from 54% in the 1980s to 57% during the 2000s; - new biopharmaceutical product approvals were more evenly distributed in six therapeutic categories during the 2000s compared to 1980-1989 and 1990-1999; and - for new biopharmaceuticals approved during 2000-2009, neither orphan or fast-track designation had a substantial impact on the average time from initiation of clinical study to FDA marketing approval.

Meantime, Janet Woodcock, director of the FDA's Center for Drug Evaluation and Research (CDER) has said she expects the agency to approve more new drugs this year than the 21 for which it granted marketing authorisations last year.

The annual total remains far below the record 53 new products approved in 1996, but Dr Woodcock says the agency is seeing more successful products coming out of investments made a decade or more ago and that she is expecting a "gradual" increase in new medicines.

"What we think we are seeing is the nadir has been reached and we're coming up the other side," she said, speaking at the Reuters Health Summit in New York.