RP101 Phase II clinical results

RP101 demonstrates efficacy and safety in Phase II study of patients with moderate-to-severe dry eye disease

  • RP101 more than doubles tear fluid production
  • Fast onset: statistically significant efficacy after just 14 days
  • All objective and subjective parameters show improvement

Stockholm, Sweden, March 12, 2020 – Redwood Pharma announces today significant improvement of objective and subjective endpoints in the Phase II study in postmenopausal women with moderate-to-severe dry eye. RP101 more than doubles tear fluid production. The objective Schirmer test reached 9.6 mm compared to the nominal 10 mm goal for the primary endpoint. Further objective and subjective endpoints demonstrate statistical improvement from baseline. 

Redwood Pharma is developing new ophthalmic pharmaceutical therapies where there are large, unmet medical needs. RP101 is a novel, topical treatment for postmenopausal women suffering from chronic, moderate-to-severe dry eye disease (DED). This Phase II product candidate consists of a low-dose estrogen analog formulated in IntelliGel to control the active substance release, and is intended to be the first hormonal therapy for DED targeted to specific underlying biological mechanisms in critical tissues in and around the eye.

By administration of the active substance 17β Estradiol 3-phosphate the product was thought to restore the normal levels of estrogen locally in the eye and consequently tearfilm production. By using the IntelliGel slow-release drug delivery platform optimal patient convenience can be achieved with only 1 or 2 instillations per day. 

RP101 ophthalmic sterile solution was tested in two different concentrations, administered once (q.d.) or twice a day (b.i.d) over a 90-day period and compared to placebo (IntelliGel). The primary efficacy endpoint was the objective measurement of basal aqueous tear secretion in millimeters during 5 minutes by the Schirmer test. Secondary endpoints including subjective measures using the Visual Analogue Scale (VAS) evaluated ocular tolerability including foreign body sensation, burning/stinging, itching, pain, sticky feeling, blurred vision, redness, tearing, eyelid swelling and photophobia.

Safety and tolerability of the treatment were also part of the study protocol.


The RP101 Phase II trial was a multi-center, double-masked, placebo-controlled study conducted in 8 clinics in Austria, Germany and Hungary. 4 groups of patients were treated over 90 days. 104 patients were included and a total of 77 patients completed the trial.

Efficacy was assessed by various primary and secondary endpoints, both objective and subjective. 

The primary endpoint of the Schirmer test of 10 mm was an aspirational goal when setting up the trial with the expectations of doubling the tear production from baseline. Median baselines of treatment groups were lower and more challenging than expected, being around 4 mm. The fact that RP101 managed to more than double production and reach 9.6 mm is statistically significant.

With 3 active groups and one placebo group (IntelliGel), objective as well as subjective measures, showed improvement, some as early as 14 days, and throughout the 90-day treatment period. Those that showed statistical improvement included Schirmer test, tear break-up time, SANDE, tearing, foreign body sensation and itching. After 3 months, all active groups show improvement for all symptoms. There were no statistical differences between the treatment groups.

From a regulatory perspective, efficacy can be demonstrated by both primary and secondary endpoints. At least one subjective and one objective endpoint are required by the US Food & Drug Administration and European Medicines Agency to achieve market authorization in their respective geographies.

The most frequent Adverse Events are also symptoms of the disease such as blurred vision, eye pain and eye irritation. No serious adverse events were reported. In brief, RP101 is considered safe.

“This study shows a consistent and pronounced benefit in objective measures of DED. Results from Schirmer test show fast onset in tear production reaching its maximum effect after 90 days of treatment. Together with the improvement of symptoms it makes an excellent candidate for further development,” states Prof. Gerhard Garhöfer, of the Medical University of Vienna, Austria, and Principal Investigator of the RP101 study.

CEO Martin Vidaeus says, “These very positive results mean that RP101 continues to reveal its commercial potential as a topical estrogen therapy for the treatment of dry eye disease that affects millions of people worldwide. As part of our ongoing discussions with potential commercial partners globally, the company will continue its efforts to find a development and commercial partner to realize the value of this asset.”

For more information:
Martin Vidaeus, CEO Redwood Pharma AB (publ.)
Tel: +46 (0) 70 232 29 29

E-mail: martin.vidaeus@redwoodpharma.com

This information is information that Redwood Pharma AB is obliged to make public pursuant to the EU Market Abuse Regulation. The information was submitted for publication, through the agency of the contact persons set out above, on March 12, 2020.

About Redwood Pharma
Redwood Pharma develops ophthalmic products for unmet medical needs. The Company’s first project is the development of drug candidate RP101 with a known active substance against chronic dry eye in postmenopausal women who have moderate to severe symptoms. With the drug delivery platform IntelliGel the release of active substances is controlled. Through the use of IntelliGel, Redwood Pharma can also improve dosing of other established drugs. Redwood Pharma’s strength lies in formulation and early clinical development. Revenues will be generated through licensing agreements with pharmaceutical companies that have capabilities to manufacture and sell commercial products worldwide.

Redwood Pharma AB (publ.) is listed on the Spotlight Stock Market (Ticker: REDW.ST, ISIN: SE008294789).

For more information visit: www.redwoodpharma.com