Yes. Elysium conducted a first-in-humans, double-blind, placebo-controlled, randomized study assessing the safety and efficacy of taking repeat doses of Basis — a combination of nicotinamide riboside (NR) and pterostilbene — in a population of 120 healthy adults ages 60-80. Participants taking the recommended dose of Basis (250 mg of NR; 50 mg of pterostilbene) saw their NAD+ levels increase by an average of 40 percent over baseline after 30 days, a number that was sustained at 60 days. Participants taking twice the recommended dose of Basis saw their NAD+ levels increase by 90 percent over baseline after 30 days and 55 percent at 60 days. Those taking the placebo saw no NAD+ increase at all. There were no serious adverse events reported in the study.
The clinical study was published in November 2017 in Nature Partner Journals: Aging and Mechanisms of Disease, an international open access journal that provides a forum for important research in the field of aging. The full study is available here: https://www.nature.com/articles/s41514-017-0016-9.