Astellas has been given the go-ahead by Japanese regulators to market a new version of its blockbuster immunosuppressant Prograf.

The Ministry of Health, Labor and Welfare has approved Graceptor, a once-daily, modified-release formulation of the drugmaker's Prograf (tacrolimus) for the suppression of organ and graft rejection, as well as graft-versus-host disease in bone marrow transplantation, the company stated. The green light comes over two years since Astellas filed a New Drug Application for the treatment in Japan.

Graceptor, which Astellas said will improve long-term compliance with its more convenient once-daily dosing option, is sold as Advagraf in Europe and the drug was launched in its first markets (the UK and Germany) in June 2007. In total, it is currently marketed in 18 countries, including Canada, but the road to approval has proved much tougher in the USA.

The Food and Drug Administration only issued an approvable letter for Advagraf in May, the second time the agency had asked for more information on the drug, having issued its first approvable letter in January 2007. Astellas had been hoping to get the new version of Prograf onto the US market before the patent on the original expired there in April. Prograf has sales of around $2 billion a year and though off-patent, no generic product has been approved as yet.

Astellas also noted that the MHLW has approved the firm’s Irribow (ramosetron) for irritable bowel syndrome in men. The drug, a serotonin 5-HT3 receptor antagonist, “improves abnormal defecation associated with the acceleration of intestinal transit”, the Tokyo-headquartered firm said.