GlaxoSmithKline (GSK) has won ‘breakthrough’ status in the US for the use of Promacta to treat people with a low number of blood cells due to anaemia.
The status, which is granted by the Food and Drug Administration (FDA), specifically covers use of the drug to treat cytopaenias in patients with severe aplastic aneamia (SAA) who have had insufficient response to immunosuppressive therapy.
Breakthrough status is the newest regulatory designation created by the FDA to speed up the approval process for significant new medicines, having been enacted as part of the 2012 FDA Safety and Innovation Act (FDASIA).
Promacta (eltrombopag) fits into this category as it is intended for use in the treatment of a serious medical condition and has already demonstrated it may have a substantial improvement over current therapies.
With this status, GSK can expect an expedited review process for the drug, as per the FDA’s Fast Track programme, as well as more intensive guidance from the regulator.
To support its application GSK used data from a phase II study involving the National Institute of Health (NIH) which investigated the use of Promacta in 43 patients with SAA – a rare condition in which the bone marrow fails to make enough new blood cells.
All these patients had been heavily pre-treated but still showed an insufficient response to immunosuppressive therapy. However, Promacta was able to demonstrate a response in these patients, leading to the FDA’s decision.
If approved, this would be Promacta’s third approval in the US following recommendations in the treatment of low blood cell counts in adults with one of two conditions: chronic hepatitis C before and during treatment with interferon, or chronic immune thrombocytopaenia when certain treatments have not worked.
GSK developed the drug with partners Ligand, which receives royalties on Promacta sales. Outside the US, the drug is known as Revolade.