Squalamine on Trial
Squalamine may have fascinating origins – originally derived from the livers of the dogfish shark – but as a treatment for wet AMD it has so far failed to have any “bite.” An antiangiogenic steroid, this small molecule drug has been shown to stop the growth of abnormal blood vessel development and reduce vascular endothelial growth factor (VEGF), showing potential in cancer therapies as well as in treatment for macular diseases.
Initial trials discovered that it inhibited neovascularization in the iris when injected intravenously, and was found to induce regression of retinopathy in mouse models.
In 2012, Ohr Pharmaceutical commenced a clinical trial assessing the effectiveness of squalamine when combined with Lucentis injections. 128 patients were given monthly Lucentis injections, and asked to use either squalamine (0.2 percent) or placebo eye drops over a nine-month period in the multi-center, randomized, double-masked clinical trial. Assessment was carried out monthly via eye examinations and optical coherence tomography (OCT) testing, and visual acuity was testing using the Early Treatment of Diabetic Retinopathy Study (ETDRS) eye chart.
At the conclusion of the trial in January 2018, Ohr CEO Jason Slakter commented, “We are very disappointed with the outcome of the MAKO study.” Why? Subjects using squalamine only achieved a mean gain of 8.33 letters from baseline versus 10.58 letters from baseline with Lucentis monotherapy, thus failing to meet the primary efficacy endpoint: mean visual acuity gain at 9 months.
Squalamine is an interesting chemical from an unusual source. Does it still have a role to play in improving eye health?