"Taxotere will continue to lead the market into 2010, but then it loses its patent, which is going to have a massive impact on its sales," Marcus Hoyle, an analyst with Decision Resources and author of the report, told United Press International.
However, Taxotere will still be the leader because "the new products that launch aren't going to come anywhere near the sales the drug has at the moment," Hoyle said.
These include Sanofi's larotaxel and Bayer Schering's tocosol paclitaxel, which are expected to launch in 2009 and make up for the sales Taxotere will lose to generic erosion.
The Decision Resources report forecasts these two drugs will each achieve peak year sales of $100 million to $150 million.
Taxotere sales are expected to drop from $1.69 billion in 2010 to $1.37 billion in 2015.
Currently, the entire taxane market is worth about $2 billion. The report projects it will peak at $2.6 billion in 2010 and will drop to around $2.4 billion by 2015.
The taxane market is expected to experience modest growth of nearly 5 percent annually through 2010 that will predominantly be driven by increasing use of Taxotere in the breast cancer and non-small cell lung cancer settings. Larotaxel and tocosol paclitaxel will also help drive growth.
A nanoparticle formulation of Abraxis/AstraZeneca's Abraxane may also help drive market growth. A phase 2 trial comparing Abraxane to Taxotere in the metastatic breast cancer setting is slated to begin this year. If Abraxane has a strong showing in this trial, it could help propel growth of the market even more, the report forecasts.
However, the taxane market is expected to begin backpedaling after 2010, experiencing negative growth of 1.5 percent per year through 2015.
Only four novel taxanes are in late-stage development, but none of these appear to have the potential to knock off the current drugs in this class.
"We don't really forecast that there's much more commercial potential to gain out of the taxane class," Hoyle said. "Any new taxane will have to achieve improved benefit in terms of efficacy and side effects in order to compete with Taxotere."
The Decision Resources report notes the example of Cell Therapeutics/Chugai's paclitaxel poliglumex, which raised the need for showing improved survival for new taxanes. Cell Therapeutics/Chugai's drug failed to show improved survival over existing chemotherapy in three phase 3 trials.
Sanofi is also working to get its obesity treatment Acomplia approved by the Food and Drug Administration and it may have gotten a boost in that effort Monday. The company announced the FDA scheduled an advisory committee meeting for the drug for June 13.
J.P. Morgan analyst Craig Maxwell sees this as a favorable move for Sanofi because it helps take the drug out of the control of Mary Parks, the head of the FDA's endocrinologic and metabolic division.
"We see this open forum as a net positive, taking Acomplia beyond Mary Parks' decision making and allowing Sanofi to present its case in front of the panel," Maxwell stated in a research report, noting that he views Parks as "out of step with the world's major regulatory authorities who have approved Acomplia."
Maxwell said he expects Acomplia to win approval for both obesity and diabetes by the FDA review completion date of July 27.
Sanofi is also the subject of rumors it will try to acquire Bristol-Myers Squibb, with which it collaborates on Plavix.
The Times of London reported Tuesday in a story based on information from unnamed sources that the company's management was split over whether it should bid for Bristol-Myers, with the chairman of the board favoring it and the chief executive officer opposed to it.
If the two companies did merge, their combined sales would rival that of Pfizer, the world's top pharmaceutical manufacturer.