Pfizer and Ipsen returned to reinvest in the metabolic disorder treatment developer, which has now raised $114m altogether.

US-based peptide therapeutics developer Rhythm closed a $41m mezzanine round yesterday that included pharmaceutical companies Pfizer and Ipsen, the former participating through its Pfizer Venture Investments unit.

The corporates were joined in the round by Deerfield Management, OrbiMed, MPM Capital, New Enterprise Associates (NEA), Third Rock Ventures and an unnamed public healthcare investment fund.

Rhythm is developing treatments for rare genetic deficiencies that cause potentially fatal metabolic disorders.

The company will use the funding to advance its lead candidate, a…