Mifamurtide: CGP 19835, CGP 19835A, L-MTP-PE, liposomal MTP-PE, MLV 19835A, MTP-PE, muramyltripeptide phosphatidylethanolamine.

Mifamurtide is a conjugate of muramyl tripeptide linked to dipalmitoyl phosphatidyl ethanolamine; the phospholipid facilitates incorporation of the peptide into liposomes. The agent stimulates macrophages to seek out and destroy cancer cells. The compound was originated by Novartis (formerly CIBA-Geigy), and is being developed by IDM Pharma for osteosarcoma. Mifamurtide is being reviewed by regulatory authorities in the US and EU for this indication.CIBA-Geigy originally developed mifamurtide in the early 1980s and the agent was subsequently outlicensed to Jenner Biotherapies in the 1990s. IDM Pharma acquired the rights to the drug from Jenner in April 2003.IDM and Genesis Pharma have entered into an exclusive licensing and marketing agreement for mifamurtide in South East Europe. Under the agreement terms, IDM will receive an upfront fee from Genesis, as well as milestone payments on reaching certain sales levels in the territory. Medison Pharma signed an agreement with IDM Pharma for the sales and marketing of mifamurtide in Israel. IDM will receive an upfront license fee from Medison and will be entitled to receive a milestone payment upon regulatory approval of the agent in Israel, as well as royalties on net sales.IDM outlicensed exclusive marketing rights for mifamurtide in the UK and Ireland to Cambridge Laboratories in June 2005. In exchange, IDM is entitled to an upfront license fee and milestone payments prior to launch, as well as royalties calculated on product sales.Previously, Chiron Vaccines (a joint venture between Novartis and Chiron formed in 1995) investigated mifamurtide as an adjuvant in HIV gp120 vaccine; however, development has been discontinued.IDM Pharma will purchase approximately 7.1 million shares of its common stock to raise approximately $US23.5 million in net proceeds. The company intends to use the funds for working capital and corporate purposes, including the company's activities related to gaining marketing approval of mifamurtide in the US and Europe. Following the announcement by ODAC in May 2007, IDM Pharma decided to amend the NDA for mifamurtide with additional vital status data from the completed phase III trial. This data was not available at the time the original filing was made, and the company believes that capturing this supplemental data will overcome the need for additional trials, further confirm the overall survival benefit of mifamurtide in osteosarcoma, and provide evidence for approvability. IDM Pharma intends to analyse the additional follow-up data and submit an amendment to the agency by the first quarter of 2008; the company is also working on addressing other concerns raised by the US FDA in the non-approvable letter. The US regulatory submission included safety and efficacy data from NCI-funded phase III trials in 678 patients with osteosarcoma conducted by the Pediatric Oncology Group and the Children's Cancer Group in over 147 US centres. The NDA also included safety and biological effects data of mifamurtide from 17 phase I and II studies in 248 patients conducted by Ciba-Geigy. In the EU, IDM Pharma filed a MAA with the EMEA in November 2006 for approval of mifamurtide (Mepacttrade mark) in combination with postoperative chemotherapy for the treatment of patients with newly diagnosed osteosarcoma following complete surgical resection. The company expects that the EMEA will make a decision regarding marketing approval for mifamurtide by the end of 2007. Mifamurtide has orphan drug status for the treatment of osteosarcoma in the US and EU.