Pfizer’s tyrosine kinase inhibitor Bosulif has been approved in the EU as an additional line of treatment for patients with chronic myelogenous leukemia (CML).
Bosulif (bosutinib) has been given conditional approval – which is renewable annually – to treat adult patients with Philadelphia chromosome-positive CML who are in the chronic, accelerated or blast phases of the disease.
But the green light limits Bosulif’s use to patients who have already been treated with one or more other tyrosine kinase inhibitors and who are not considered candidates for first-line therapy with Novartis’ Glivec (imatinib), as well as Bristol-Myers Squibb/Otsuka’s Sprycel (dasatinib) and Novartis’ Tasigna (nilotinib) which are approved as second-line treatments.
Conditional approval is given where an urgent public health need exists, and a drug in development promises significant health benefits, but full safety or efficacy testing has not been completed.
The treatment of CML was transformed by the arrival of Glivec onto the market in 2001 but, while survival improved, the development of resistance to therapy and disease progression has meant there is a need for additional lines of drug therapy.
“It’s critical to have additional treatment options for CML patients, because each patient responds to therapy differently and has unique needs,” commented Carlo Gambacorti-Passerini of S. Gerardo Hosipital in Milan, Italy, who was a lead investigator in Bosulif’s registration study.
“Based on my experience with Bosulif, I believe this once-daily treatment, with its distinct safety profile, offers an important new alternative,” he added.
Bosulif was approved in the US last September on the back of a single 546-patient study which showed that – as a second-line therapy after Glivec – Bosulif achieved a major cytogenetic response in 34 per cent of patients, compared to 27 per cent with Sprycel or Tasigna.
Other candidates are coming through the pipeline for CML, however, including Ariad’s ponatinib, which was submitted for approval in the US and Europe last year, which has a slightly different mechanism of action than the current crop of treatments, as well as Cephalon/Hospira’s Omapro (omacetaxine), BioSante Pharma’s GVAX and Deciphera’s ABL inhibitor rebastinib (DCC-2036).