Clearside completes enrollment in SAPPHIRE Phase 3 trial of CLS-TA in RVO


Clearside Biomedical (NASDAQ:CLSD) has completed patient enrollment in its Phase 3 SAPPHIRE clinical trial of suprachoroidal CLS-TA used in combination with intravitreally-administered Eylea for the treatment of retinal vein occlusion (RVO).

The multi-country SAPPHIRE randomized Phase 3 clinical trial has enrolled 460 patients who are naïve to pharmacologic treatment for RVO, an aggressive eye disease resulting from an occlusion in a vein carrying blood out of the retina. The blockage can lead to the rapid onset of symptoms, including sudden declines in vision.

The SAPPHIRE study will assess whether using suprachoroidal CLS-TA in combination with intravitreal Eylea may offer an opportunity for earlier improved visual outcomes for RVO patients, compared with Eylea monotherapy. It is also designed to evaluate required treatment frequency for the combination arm, compared to the Eylea-alone control arm, over the course of the trial.    
In a statement, Daniel White, president and CEO, said the company expects to report top-line eight-week primary endpoint data from the SAPPHIRE trial in the fourth quarter of 2018.

In the earlier Phase 2 TANZANITE trial in RVO, suprachoroidal CLS-TA used with Eylea showed the potential to provide better vision, faster onset of action and a longer duration of action than treatment with Eylea alone.

In TANZANITE, 61% of patients in the combination arm gained at least 15 letters on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, or three lines of vision, at eight weeks, compared with 39% of patients in the control arm.

“Based on the observations from the TANZANITE trial, we believe the SAPPHIRE study has the potential to show that using suprachoroidal CLS-TA with an intravitreal anti-VEGF agent may offer an opportunity for both improved visual outcomes and a reduced treatment burden for RVO patients,” Mr. White said.

SAPPHIRE is the first of two ongoing Phase 3 trials of suprachoroidal CLS-TA with an intravitreal anti-VEGF agent in patients with RVO. The second Phase 3 RVO study, TOPAZ, was initiated in March 2018 and is evaluating suprachoroidal CLS-TA used together with one of two other intravitreal anti-VEGF agents, Lucentis or Avastin, in treatment naïve patients with RVO. 

If the primary endpoints are met in both SAPPHIRE and TOPAZ, Clearside intends to seek a class label in the U.S. under which suprachoroidal CLS-TA could be used with any approved intravitreal anti-VEGF agent for the treatment of RVO.

Melane LaBelle Sampson