Based on the information provided, Nivolumab is a medication that is also known as Opdivo and is used for the treatment of various types of cancer. The drug is a programmed death receptor-1 (PD-1) inhibitor, which helps the body's immune system to fight against cancer cells [1][2].

The manufacturing of Nivolumab is primarily done by Bristol Myers Squibb (BMS), a global biopharmaceutical company that discovers, develops, and delivers innovative medicines to patients with serious diseases [3]. According to the company's website, BMS is committed to advancing the science of immuno-oncology and expanding the therapeutic use of Nivolumab to help patients with cancer [3].

However, it is important to note that while BMS is the primary manufacturer of Nivolumab, other pharmaceutical companies may also manufacture and distribute the drug under license from BMS. This is a common practice in the pharmaceutical industry, where companies enter into licensing agreements to manufacture and distribute drugs that are still under patent protection [1].

To confirm which other companies may be manufacturing Nivolumab, it would be necessary to conduct further research or contact BMS directly for more information. The drug patent watch website provided as a source does not list any other manufacturers for Nivolumab [1].

In summary, while Bristol Myers Squibb is the primary manufacturer of Nivolumab, other companies may also manufacture and distribute the drug under license from BMS. Further research or contacting BMS directly would be necessary to confirm additional manufacturers.

Sources:
[1] <https://www.drugpatentwatch.com/p/biologics/ingredient/Nivolumab>
[2] <https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9119881/>
[3] <https://www.bms.com/>