Otsuka refiles 'digital' medicine for mental illness

Just over a year ago the FDA refused to approve the combination of Otsuka's Abilify with an ingestible sensor capsule developed by Proteus, saying it wasn't happy with the risk analysis for the digital medicine.

Now, Otsuka is ready to seek US approval once again and should hear back from the US regulator in the fourth quarter of this year. Abilify is approved to treat schizophrenia, bipolar disorder and major depressive disorder.

The so-called 'digital medicine' consists of Otsuka's Abilify (aripiprazole) embedded with Proteus' ingestible sensor that is the size of a grain of sand, which records medication ingestion. With patient consent the sensor shares the information with the patient's healthcare providers and selected loved ones.

The drug/device tie-up was knocked back by the FDA last year with a request for additional information including data on the product's performance under the conditions in which it is likely to be used, as well as 'human factors investigations' to evaluate any user-related risks and to confirm that patients will be able to use it safely and effectively.

"If approved, this digital medicine would securely measure patient medication-taking patterns, as well as select physiological data and self-reported behavioural information," said Otsuka in a statement. "This information would help enable individuals along with their healthcare professional team to better manage their serious mental illness."

The soluble sensor is activated when it reaches stomach fluids, and communicates with a wearable patch that detects and records the ingestion of the tablet as well as select physiological data.

Proteus' digital medicine has already been approved in the US, Europe and China for use on its own, but if the current filing goes through it would be the first time that the technology would be cleared for use alongside a drug therapy.

Otsuka is hoping that the drug/device combination will give Abilify - which has already lost patent protection - a new lease of life given that sales slumped 48% last fiscal year to 17.8bn yen ($159m). The company's long-acting formulation Abilify Maintena is however still in the growth phase, rising 22% to 136bn yen, while Otsuka has a follow-up drug called Rexulti (brexpiprazole) that rose 58% to 101bn yen.