The FDA granted breakthrough therapy status to AbbVie’s experimental chronic lymphocytic leukemia drug venetoclax.

The drug is being considered as a treatment for chronic lymphocytic leukemia patients with the 17p gene deletion who have been previously treated.

An approval would add competition to treatments including Gilead Sciences’s Zydelig and Imbruvica, which is co-marketed by Johnson & Johnson and Pharmacyclics.

AbbVie and Roche’s Genentech subsidiary collaborated on the medication.

AbbVie expects to submit the drug to the FDA by the end of the year.