FDA Grants Orphan Drug Designation for BN-Brachyury for the Treatment of Chordoma

Phase II study in metastatic chordoma to initiate in second half of 2018

On 2 May 2018, Bavarian Nordic A/S announced that the US Food and Drug Administration (FDA) has granted orphan drug designation to the company’s novel cancer vaccine BN-Brachyury for the treatment of chordoma. 

BN-Brachyury is a novel prime-boost cancer immunotherapy candidate, developed in collaboration with the US National Cancer Institute (NCI). The product candidate consists of a prime (MVA-BN) and a booster dose (fowlpox or FPV), which have been modified to express brachyury and to encode three costimulatory molecules, known as TRICOM. Brachyury is a tumour-associated antigen that is overexpressed in major solid tumours, as well as several rare, ultra-orphan cancer indications, and is reported to play a key role in the metastasis and progression of tumours. Tumours that overexpress brachyury are believed to be highly resistant to standard therapies, including radiation and chemotherapy, and are associated with decreased survival rates.

According to a recent article published by Miettinen M, et al. in the Am J Surg Pathol1, an immunohistochemical study showed that Nuclear Brachyury Expression is consistent in chordoma and emerged as a “sensitive and fairly specific” diagnostic marker. A growing body of literature suggests that it contributes significantly to chordoma pathogenesis. 

A phase II study in patients with metastatic chordoma will initiate in the second half of 2018, enrolling up to 25 patients, with a goal of increasing overall response rates for patients receiving the BN-Brachyury vaccine in combination with radiation therapy.

In early 2018, the Bavarian Nordic A/S initiated an open-label phase I trial to evaluate the safety and tolerability of the BN-Brachyury vaccine. This trial is currently enrolling up to 10 patients with metastatic or unresectable, locally advanced malignant solid tumours. The primary endpoint of the study is safety and tolerability, and secondary endpoints include immunologic responses, as measured by an increase in brachyury-specific T-cells and other tumour-associated antigens. 

There is a severe lack of effective therapies for population of patients with chordoma. Chordoma is a unique tumour where the brachyury protein is universally overexpressed; which presents an opportunity to test the vaccine in an optimally targeted manner.

The FDA's Office of Orphan Drug Products grants orphan status to support development of medicines for safe and effective treatment, diagnosis or prevention of rare diseases or disorders. Orphan drug designation may provide certain benefits, including a seven-year period of market exclusivity if the drug is approved, tax credits for qualified clinical trials and an exemption from FDA application fees. 

Chordoma is diagnosed in just one in one million people per year. That means that about 300 patients are diagnosed with chordoma each year in the US, and about 700 in Europe. At any given time, it is estimated that fewer than one in 100,000 people are living with chordoma.

Chordoma develops along the spine, with presentation occurring at one of three main sites: sacrum, mobile spine, or the clivus (skull base). It shares many characteristics with sarcomas but is often characterised as a bone tumour. Chordomas are complicated tumours to treat, due to the proximity to and/or involvement with critical structures such as the brainstem, spinal cord, and important nerves and arteries.

The Bavarian Nordic A/S announcement contains forward-looking statements. 

Citation

  1. Miettinen M, Wang Z, Lasota J, et al. Nuclear Brachyury Expression Is Consistent in Chordoma, Common in Germ Cell Tumors and Small Cell Carcinomas, and Rare in Other Carcinomas and Sarcomas: An Immunohistochemical Study of 5229 Cases. Am J Surg Pathol 2015; 39(10):1305-1312.