Opthea achieves positive vision trial, eyes further clinical trials

Biopharmaceutical company Opthea (ASX: OPT) has taken an affirmative step towards commercialising its OPT-302 combination therapy after publishing positive phase 2b clinical trial results that included 366 patients.

With the results published the biopharma company claims that PT-302 may emerge as a combination treatment that can offer better vision gains than currently available care with further registrational trials “clearly justified”, the company said.

From a financial perspective, Opthea also got a boost by completing the clinical trial six months ahead of schedule which led to “substantial cost savings”.

Furthermore, Opthea said it’s fully funded through the remaining phase 2b trial close-out activities and has sufficient capital to prepare for registrational phase 3 trial activities.

Trial results

In a statement to the market, Opthea said the recent trial demonstrated that OPT-302 combination therapy met the primary endpoint of superiority in mean visual acuity gain at 24 weeks compared to Lucentis monotherapy in treatment-naïve patients with wet age-related macular degeneration (AMD).

Wet AMD is a disease characterised by the loss of vision of the middle of the visual field caused by degeneration of the central portion of the retina – typically caused by abnormal growth of blood vessels below the retina, and the leakage of fluid and protein from blood vessels.

According to Opthea, the phase 2b trial was randomised, double-masked and sham-controlled with participants allocated to two intravitreal doses of OPT-302 at 0.5mg and 2mg dosages.

The drug was administered monthly in combination with 0.5mg Lucentis over 24 weeks, versus a control group that received standard of care 0.5mg Lucentis administered monthly.

Patients administered with the 2mg doses of OPT-302 combination therapy gained a mean of 14.2 letters of vision from baseline on the Early Treatment of Diabetic Retinopathy Study (ETDRS) standardised eye chart, compared to 10.8 letters in the control group – a statistically significant benefit of 3.4 letters.

“In testing for superiority against very intensive anti-VEGF-A therapy, the bar was set high. Despite this, OPT-302 combination therapy showed statistical superiority for the most accepted and sensitive primary efficacy outcome – mean visual acuity,” said Professor Tim Jackson, chief investigator of the study, and consultant ophthalmic surgeon at King’s College London.

Mr Jackson added that “key secondary endpoints were very supportive of the primary outcome, and safety was favourable. Taken together, these results indicate that combined suppression of VEGF A, C and D has considerable potential as a novel treatment for wet AMD.”

Secondary benefits

In addition to meeting the primary outcome, secondary endpoint results were also supportive and amiable. From the 2mg OPT-302 combination group, 45% gained 15 or more letters from baseline to week 24, compared to 40.5% of patients in the Lucentis control group.

Opthea also said that excess retinal thickness measured on spectral domain optical coherence tomography was decreased and normalised consistently across all treatment groups by week 24.

As one of the study investigators that participated in conducting the trial and interpreting its results, Dr Pravin Dugel said that to achieve Opthea’s highly significant result and meaningful additional clinical efficacy with OPT-302 was a “great achievement”.

“OPT-302 has the potential to be a game-changer in the treatment landscape, not just for wet AMD but also for other debilitating retinal vascular diseases where there remains a significant unmet medical need for more efficacious therapies.

“The phase 2b trial results demonstrate for the first time, that clinically meaningful gains in visual acuity approaching three lines of vision (15 letters) may be possible with OPT-302 combination therapy targeting a novel mechanism of action,” said Dr Dugel.

“The results further support our conviction that OPT-302, the first ‘Trap’ inhibitor of vascular endothelial growth factors C and D designed specifically for the eye, can improve patient outcomes in wet AMD and other retinal vascular diseases,” said Dr Megan Baldwin, chief executive officer and managing director of Opthea.

In early morning trade, Opthea’s share price rocketed almost 114% to reach $1.85.