Switzerland has granted Novartis the first regulatory nod for Tasigna (nilotinib) in the treatment of chronic myeloid leukaemia in patients who are unable to take its current blockbuster in the field, Gleevec/Glivec (imatinib).

The thumbs up has been based on Phase II data showing high response rates amongst these patients when taken twice-daily. Tasigna inhibits the Bcr-Abl protein manufactured the abnormal Philadelphia chromosome, which has been found to be the key driver of cancer-causing white blood cells in this condition. Results from the studies have shown Tasigna reduced or eliminated the abnormal chromosome in 42% of Gleevec-resistant patients in the chronic phase of the disease and 31% of patients in the accelerated phase.

Novartis, which notes the development programme for Tasigna was a record five years from synthesis to first regulatory approval, also expects to receive additional decisions from Europe and the USA later on this year, despite having recently seen the review period extended three months by the latter's Food and Drug Administration. A regulatory submission was completed in Japan during the second quarter of the year.

But it's not planning on resting on its laurels and is also hoping to initiate additional Phase III studies of Tasigna this year in CML patients who are responding sub-optimally to other therapies, as well as in newly-diagnosed patients. A registration study in gastrointestinal stromal tumours - the first indication sought for Gleevec - is also underway.

CML is one of the four most common types of leukaemia and is responsible for around 15% of all leukaemia cases worldwide. Around 95% of CML patients have the Philadelphia chromosome.