Could a common vitamin boost immunotherapy for melanoma?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * 1\. Signed written and voluntary informed consent. * 2\. Age ≥18 years, male or female. * 3\. Have histologically or cytological documented unresectable stage III or stage IV metastatic melanoma (AJCC 8th edition). * 4\. Have not received any previous systemic treatment for advanced melanoma, including chemotherapy, immunotherapy or targeted therapy. * 5\. Be willing and able to provide stool and blood specimen for analyses at protocol specified time points. * 6\. Performance status of 0-2 on the Eastern Cooperative Oncology Group (ECOG) performance scale. * 7\. Not pregnant for females of child bearing potential as indicated by negative serum or urine pregnancy test within 72 hours of study start Exclusion Criteria: * 1\. Subjects unable to swallow orally administered medications or any subjects with gastrointestinal disorders likely to interfere with absorption (e.g. bowel obstruction, short gut syndrome, blind loop syndrome, ileostomy, etc.). Subjects with colostomies may be enrolled. * 2\. Subjects with inflammatory bowel disease. * 3\. Any condition that, in the opinion of the Investigator, would interfere with subject safety, or evaluation of the collected specimen and interpretation of study result. * 4\. Pregnant or planning to get pregnant in the next 6 months. * 5\. Female patient breastfeeding. * 6\. Allergy to the investigational product (or its non-medicinal ingredients)- Calcium Pantothenate (stearic acid, Hydroxypropyl methylcellulose) or Immune checkpoint inhibitors (or its non-medicinal ingredients)- Nivolumab (Hydrochloric acid, mannitol (E421), pentetic acid, polysorbate 80, sodium chloride, sodium citrate, sodium hydroxide) and Ipilimumab (diethylene triamine pentaacetic acid (DTPA), mannitol, polysorbate 80, sodium chloride, Tris-hydrochloride, sodium hydroxide, hydrochloric acid