Major drug makers Roche and AstraZeneca have been granted breakthrough therapy designations (BTD) by the US Food and Drug Administration (FDA) for treatments in multiple sclerosis (MS) and bladder cancer, respectively.

Roche’s Ocrevus (ocrelizumab) is the first investigational drug to receive the designation for MS. Ocrelizumab, a human monoclonal antibody, is designed to selectively target specific immune cells – CD20-positive B cells – which are thought to be a key contributor to nerve damage.

The drug treats primary progressive MS (PPMS), a debilitating form of the disease characterized by steadily worsening symptoms with no approved treatment. Roche said it will submit Phase III data to global regulators in the first half of this year.

AstraZeneca’s durvalumab (MED14736) is also an investigational human monoclonal antibody directed against programmed death ligand-1 (PD-L1) for treating patients with advanced metastatic forms of bladder cancer, but also other cancers. The company said patients suffering from metastatic bladder cancer have a five-year overall survival rate of less than 15%.

The BTD, which is the third the FDA has granted AstraZeneca for oncology treatments to date, is based on early clinical data from a Phase I trial of patients.

In addition to bladder cancer, durvalumab is also being investigated for treatment of lung, head and neck, liver and blood cancers.

Breakthrough designation is designed to expedite the development of new drugs for treating serious conditions where they have shown encouraging results from early clinical trials.