May 9 (Reuters) - Bristol-Myers Squibb Co said on Thursday its immunotherapy Opdivo failed to meet the main goal of a late-stage trial testing it in patients with an aggressive form of tumor that affects the brain or the spine.

Opdivo, used in combination with radiation therapy, failed to extend survival in patients with glioblastoma multiforme (GBM), when compared with the chemotherapy temozolomide and radiation therapy.

GBM is the most common type of tumor that forms in the nervous system. The standard treatment involves surgery, along with radiation therapy and chemotherapy.

Opdivo is Bristol's growth driver and brought in $1.8 billion in first-quarter sales.

The drug is already approved as a treatment for types of skin, lung and kidney cancers, and faces fierce competition for other immunotherapies including those from rivals Merck & Co Inc and Roche Holding. (Reporting by Manas Mishra in Bengaluru; Editing by Shailesh Kuber)