AstraZeneca gains reprieve for once-failed cancer drug

AstraZeneca ($AZN) has seen its experimental thyroid cancer drug selumetinib gain orphan status in the U.S. a year after it failed in a key trial to help patients with a rare type of melanoma.

The Anglo-Swedish drugmaker said in a release that the FDA has granted orphan drug designation for its MEK 1/2 inhibitor selumetinib (AZD6244, ARRY-142886) for adjuvant treatment of patients with late-stage differentiated thyroid cancer (DTC). The drug was originally developed by Array BioPharma.

It’s being studied in a subpopulation of patients who do not respond well to the current standard of care, radioactive iodine (RAI).

Dr. Sean Bohen, EVP of global medicines development and CMO at AstraZeneca, said in a release: “Uptake of RAI is crucial for patients with thyroid cancer where no other therapies have proven beneficial. Selumetinib could significantly enhance currently available treatment options for these patients. The Orphan Drug Designation is an important achievement as we advance our development plans for this potential treatment in differentiated thyroid cancer.”

Orphan status is awarded to medicines promising significant benefit in treating rare, life-threatening diseases, and the designation provides companies with special development and market exclusivity incentives.

Gaining this designation is something of a reprieve for AstraZeneca, as selumetinib failed to meet its goal in a late-stage trial for uveal melanoma--a rare type of eye cancer believed to result from high sun exposure--in July last year.

Selumetinib inhibits the MEK pathway in cancer cells to prevent tumor growth and has a similar mechanism of action to Novartis’ ($NVS) recently acquired MEK inhibitor Mekinist, which has a license in patients with certain forms of melanoma.

Astra’s drug is currently being tested in the Phase III Astra trial in patients with DTC who are at high risk of recurrence.

Recent results from a midstage study of selumetinib in patients with advanced thyroid cancer showed “clinically meaningful increases” in iodine uptake and retention in patients with thyroid cancer that was refractory to RAI, according to the company.

In addition to DTC, selumetinib is also in late-stage testing for KRAS-mutant advanced non-small cell lung cancer, as well as a Phase II registration trial of young patients with neurofibromatosis Type 1, a rare genetic condition that causes tumors to grow on nerve tissue.

This drug is however seen as less important toward AstraZeneca’s 2020 sales goal than its recently approved lung cancer treatment Tagrisso, as well as its checkpoint inhibitor durvalumab.

This is in fact the second drug from the company focused on thyroid cancer: Back in 2012, the drugmaker gained European approval for Caprelsa, the first licensed treatment for advanced medullary thyroid cancer.

- check out the release