Larimar Therapeutics shares tumbled 54.6% in premarket trading.Larimar Therapeutics, Inc. (“Larimar”) (Nasdaq: LRMR), a clinical-stage biotechnology company focused on developing treatments for complex rare diseases, announced that it has received feedback from the U.S. Food and Drug Administration (FDA) regarding the clinical hold on Larimar’s CTI-1601 program. FDA stated it is maintaining its clinical hold at this time and that additional data is needed to resolve the clinical hold. Larimar is further analyzing previously completed studies, and is evaluating if additional studies are warranted. The Company also intends to engage FDA to determine how best to provide these data. Larimar is currently reassessing guidance on the timing of the planned Jive open-label extension and pediatric multiple-ascending dose clinical trials as it works to meet the agency’s request.