Palovarotene (Ro 3300074) is an agonist of nuclear retinoic acid receptor γ (RAR-γ).

Palovarotene inhibits post-traumatic chondrogenesis and osteogenesis and mitigated trauma-induced ectopic bone formation. Palovarotene inhibits subcutaneous and intramuscular heterotopic ossification (HO) in mice. Palovarotene (1 mg/kg/day ) is given orally for 14 days starting on a postoperative day (POD) 1 or POD-5, and HO amount wound dehiscence and related processes are monitored for up to 84 days post-injury. Compared to vehicle-control animals, Palovarotene significantly decreases HO by 50 to 60% regardless of when the treatment started and if the infection is present[1]. Starting from day 1 of injury, half of the Acvr1cR206H/+ mice are treated with Palovarotene by daily gavage for 14 days and the other half received a vehicle as control. Analysis by mCT and 3D image reconstruction at day 14 shows that large HO tissue masses have formed in the targeted leg of Acvr1cR206H/+ mutant mice receiving the vehicle, but HO formation is greatly diminished in Palovarotene-treated companions by more than 80% based on bone volume/total volume quantification[2].