Graybug Vision releases preliminary topline results of Phase 2b ALTISSIMO trial

Graybug Vision, Inc. has reported preliminary topline data from a 12-month treatment phase of its Phase 2b ALTISSIMO trial of GB-102 for the treatment of wet age-related macular degeneration (AMD).

GB-102 is the company’s proprietary microparticle depot formulation of sunitinib malate that is injected intravitreally.

The ALTISSIMO trial consists of a masked, controlled phase 2b dose-ranging study of two GB-102 doses with a single arm control of patients on aflibercept, according to a company release.

The injections were distributed across 33 study sites in the U.S.

Primary endpoint includes median time to first supportive therapy with a VEGF inhibitor, while secondary endpoints are pharmacodynamics measures of mean of change of best-corrected visual acuity (BCVA) from baseline and mean of central subfield thickness (CST) of the retinae from baseline, the release stated.

The initial target of the trial was to evaluate two separate doses of GB-102 — 1 mg and 2 mg — injected every six months and compared to aflibercept injected every two months.

Following results of an interim safety analysis and the initial dose, however, the 2 mg dose was discontinued. All patients in that arm were then switched to 1mg for their second dose, according to the release.

An examination of the ALTISSIMO 1 mg arm shows that the primary endpoint of median time to first supportive therapy was 5 months.

Additionally, 48% of the patients did not require supportive therapy for at least six months, and 62% did not require supportive therapy for at least four months more, at least once during the trial, according to the company.

When compared, the 1 mg dose performed more positively than the 2 mg dose.

In all, the GB-102 1 mg dose was well-tolerated by patients. The majority of drug-related adverse events were mild to moderate, and medication was detected in the anterior chamber in less than 10% of the 1 mg injections.

No adverse events required surgical intervention, no vision-threatening inflammation was observed, and there were no reported of increased IOP levels, per the release.

The measurements of secondary endpoints included: CST in the GB-102 1 mg arm was consistent with the study control arm.

The mean change from baseline for BCVA for all 20 completers was approximately nine letters lower across all time points, on average, than that observed in the study control arm.

At the conclusion of the treatment phase, 80% of patients treated with GB-102 reported being equally or more as satisfied as the satisfaction expressed by those treated with aflibercept.

A six-month extension has been added to the trial, in which 28 of the 50 patients who completed the 12-month injections were eligible and agreed to continue with masked clinical monitoring. These patients will continue with monthly visits up to a maximum of six months, or until they require additional supportive therapy.

At present, 22 patients have completed two months or more of the six-month extension period with a need to receive further treatment.

Next steps for the trial will be determined following completion of a full analysis on the ALTISSIMO results, expected in Q2.