Roche's leukaemia drug granted breakthrough status

A new drug from Roche and AbbVie has been given 'breakthrough' status by the FDA for patients with a hard to treat sub-type of chronic lymphocytic leukemia (CLL).

The companies are currently developing venetoclax (RG7601, GDC-0199/ABT-199), for people who have relapsed or refractory CLL, and who have the genetic abnormality known as 17p deletion.

This genetic sub-type is found in 3-10 percent of previously untreated cases and approximately 30-50 percent of relapsed or refractory cases. People with 17p deletion CLL have poor results with conventional chemotherapy regimens and a median life expectancy of less than three years.

The treatment of blood-based cancers is currently undergoing a revolution, with many new medicines coming on to the market, including several groundbreaking drugs for CLL.

Most notable among these are Pharmacyclics and Janssen's co-marketed Imbruvica (ibrutinib) which was approved in the wider CLL population, and then gained US approval for use in 17p deletion patients in July last year. Gilead's rival Zydelig (idelalisib) is another new CLL drug, and gained European approval for first line use in 17p deletion patients last September.

Roche's own competitor in the field Gazyva/Gazyvaro (obinutuzumab) is the third of the newly launched CLL treatments, but hasn't yet secured a licence in 17p deletion patients, hence its new drug could help it compete in this already competitive market segment.

Analysts expect Imbruvica to hit sales of around $3.3 billion by 2018, with Zydelig forecast to reach peak annual sales of up to $2 billion.

Venetoclax is being developed by the partners in phase 2 and phase 3 for CLL, and in phase 1 and phase 2 for several other blood cancers. AbbVie recently acquired Pharmacyclics for $21 billion, making it and its co-developer Roche direct rivals in the CLL field.