Pfizer is considering a deal with Japan’s Taisho Pharmaceutical which could see the New York-headquartered drugs giant license the rights to an investigational compound aimed at treating schizophrenia.

The firms have signed a letter of intent with regard to TS-032, a novel metabotropic glutamate receptor agonist discovered by Taisho which shows potential as a treatment for schizophrenia and is currently at the pre-clinical stage. Under the terms of the proposed deal, Taisho would grant exclusive development and commercialisation rights outside Japan for TS-032 to Pfizer, whose present schizophrenia franchise is headed by Geodon (ziprasidone).

If the agreement does get signed, Taisho will receive an initial payment of $22 million, plus development and sales milestone payments as well as royalties. The companies were at pains to point out that although the characteristics of mGluR “are still only partly understood”, it is believed to play a role in the transmission of glutamate and other substances in the brain. Abnormalities in the neurotransmission through mGluR may be one cause for symptoms related to schizophrenia as well as other central nervous system disorders, they added.

A licensing deal with the world’s largest drugmaker, especially for a compound that is at such an early stage of development, would be a major coup for Taisho which is best-known for its over-the-counter products. The firm says it has been “steadily strengthening its prescription drug R&D” and these efforts “have seen it make progress with several original projects.” Taisho added that it is hoping to sign more alliances to bolster its prescription pharmaceuticals business.

As for Pfizer, a deal would mark a return to schizophrenia research almost a year after it decided to discontinue its role in the development of asenapine with Akzo Nobel's Organon unit By Kevin Grogan