It was Prof. Birkmayer who bought the stable form of NADH to the market, you can find his products here[0]. As mentioned it’s not a peptide and works quite well especially for older people who can benefit from the increased energy delivery to the cells. The unstable form in a liquid can be injected, but I would be very careful about where it was produced, how it was transported and how it was stored.

The whole peptide hype is very interesting and I can’t wait until well studied cheap over the counter options hit the market.

0. https://birkmayer-nadh.com/