Cytotoxic therapies to feel sting of generics, says Datamonitor

Cytotoxics make up the second largest selling class of cancer therapeutics. However, given the relative maturity of this therapeutic class, generic incursion will cause a decline in total cytotoxic market value after it reaches a peak of $16.5bn (Euro 12.9bn) in seven major markets (France, Germany, Italy, Japan, Spain, UK and US) in 2013, according to independent market analyst Datamonitor.

Sales of the 25 cytotoxic therapy cancer brands that are currently available in the seven major markets in 2007 totalled $10bn (â"šÂ¬7.8bn), states Datamonitor's report Commercial Insight: Cytotoxic Therapy Cancer Brands - Looming patent expiries limit market growth.

"Even though targeted therapies are becoming more and more popular, cytotoxics remain the backbone of cancer treatment," saids Datamonitor oncology analyst Chandni Surti. "As the incidence of cancer continues to rise with the ageing population, the use of effective cytotoxic therapies is likely to remain strong."

Sanofi-Aventis markets four out of the 25 cytotoxic therapy cancer brands, including the two top sellers, Eloxatin (oxaliplatin) and Taxotere (docetaxel), with combined sales of $3.8bn (â"šÂ¬3.0bn) in 2007. However, said Surti, patent expiries for these leading cytotoxic brands, Eloxatin in 2007 (EU) and Taxotere in 2010 (US and EU), are likely to have a significant impact on Sanofi-Aventis's performance in the broader oncology market.

Eloxatin's patent is set to expire in Japan in May 2013 and the US in August 2016. Higher generic erosion rates are applicable in the US than in the remaining major markets, implying a greater dent in brand sales. In fact, the impact of generics is expected to reduce the cytotoxic therapy brands" overall US market share from 56% in 2007 to 31% in 2017. Despite this, Eloxatin is forecast to remain the best-selling cytotoxic therapy cancer brand in the seven major markets, achieving sales of $2.7bn (â"šÂ¬2.1bn) in 2017.

Eisai/Johnson & Johnson's Dacogen (decitabine) and Celgene/Nippon Shinyaku's Vidaza (azacitidine) are antimetabolite cytotoxic agents approved in the US for myelodysplastic syndromes (MDS). Following its launch in 2006, Dacogen has become a major competitive threat to Vidaza, which was launched in 2004. Dacogen made $137m (â"šÂ¬107m) in 2007, allowing it to quickly catch up with the sales of Vidaza.

Datamonitor forecasts Dacogen sales to grow in line with Vidaza over the forecast period of 2007 to 2017. "Both hypomethylating agents seek EU approval for use in MDS and Datamonitor forecasts their launch to occur around the same time in 2009," said Surti. "The increase in sales forecast for Dacogen ($1.3bn; â"šÂ¬1.0bn) and Vidaza ($1.2bn; â"šÂ¬935m) helps boost sales of the total cytotoxic therapy cancer brand market to $14.9bn (â"šÂ¬11.6bn) in 2017."