Shire has entered an agreement with Parion Sciences to gain exclusive worldwide rights to develop and commercialise P-321, an investigational epithelial sodium channel (ENaC) inhibitor indicated for dry eye treatment in adults.

P-321 is a novel small molecule that inhibits ENaC, which is believed to block the absorption of tears, and helps to keep the ocular surface hydrated.

The agreement will enable Shire to lead the development of P-321, providing Parion  with the opportunity to co-fund.

Shire CEO Flemming Ornskov said: “Ophthalmics is a continued focus for Shire, and the programme for P-321 will benefit from our development and commercial infrastructure and expertise.

“This is an opportunity to apply our knowledge and experience from ophthalmics and dry eye disease for further innovation in this space. If approved, P-321 would expand our eye care portfolio.”

"Ophthalmics is a continued focus for Shire, and the programme for P-321 will benefit from our development and commercial infrastructure and expertise."

The specific terms of the agreement were not divulged by the companies, however, Shire will make an initial $20m upfront licence payment with a further $20m payment as the near-term development achieves specific milestones.

Parion will also be entitled to receive additional potential milestone payments, with a total deal value of up to $535m.

The agreement provides Parion with the option to co-fund through further development stages against double-digit royalties.

A Phase I/IIa, placebo-controlled, dose-escalation clinical study was conducted on 53 patients to assess the safety and tolerability of P-321 in patients affected with mild-to-moderate dry eye disease.

The company reported that positive trends were observed in the improvement of signs and symptoms of dry eye disease in subsets of patients compared to placebo, though the study was not powered to assess efficacy signals.

After consulting the higher authorities, a Phase IIb study is expected to be carried out soon.