A phase 3 clinical trial investigating the use of Actemra (tocilizumab) in giant cell arteritis (GCA) has completed enrollment, developer Genentech (South San Francisco) said, adding data is expected some time in 2016. There is currently no approved treatment for GCA in the U.S., and the only effective treatments are steroids, Genentech added.

The multicenter, randomized, double-masked, placebo-controlled study will evaluate the efficacy and safety of Actemra in patients with giant cell arteritis. Patients will be randomized to receive Actemra 162 mg subcutaneously weekly or every 2 weeks or placebo for 52 weeks, with tapering oral daily doses of prednisone according to either a 6-month or 12-month regimen. After week 52, patients in remission will stop study treatment and enter long-term follow-up, whereas patients with disease activity or flares will receive open-label Actemra 162 mg subcutaneously weekly for a maximum period of 104 weeks at the discretion of the investigator. Anticipated time on the study is 39 months.

The Dogwood phase 2 study evaluating a proprietary form of triamcinolone acetonide for the treatment of macular edema associated with non-infectious uveitis has completed enrollment, developer Clearside Biomedical (Alpharetta, Ga.) said in a news release. Top-line data from the study is expected by the end of 2015. 

The Dogwood trial is the first masked, randomized trial conducted in humans administering the compound through the suprachoroidal space. The primary efficacy endpoint of the Dogwood phase 2 clinical trial is the mean change from baseline in retinal thickness at 2 months after treatment. Secondary efficacy endpoints include visual acuity improvements at 1 and 2 months after treatment, measured by the mean change in best corrected visual acuity from baseline. Safety measures are being monitored over the 2-month observation period and include the incidence of adverse events and serious adverse events, including increases in intraocular pressure.

A pivotal phase 3 study is expected to begin enrollment in December.

At a conference last week, Stephen R. Russell, MD, University of Iowa, presented data on the 3-year durability of improvements from SPK-RPE65 for the treatment of RPE65-mediated inherited retinal dystrophies (IRDs), developer Spark Therapeutics (Philadelphia) said. 

Dr. Russell reported on the same measures of functional vision and light sensitivity in a cohort of subjects from an earlier phase 1 trial. There was a mean improvement in the functional vision of intervention subjects (n=20) of 1.9 specified lux levels, compared with an improvement of 0.2 specified lux levels in control subjects (n=9) as measured by the change in bilateral mobility testing (MT) between baseline and 1 year in the modified intent-to-treat (mITT) population. The mITT population (n=29) included all subjects that received SPK-RPR65 and only those who continued beyond the baseline study visit. Two subjects in the intent-to-treat (ITT) population (n=31) that were randomized but never received SPK-RPE65 were excluded from this efficacy analysis. Thirteen of the 20 subjects receiving SPK-RPE65 were able to pass the MT at 1 lux at year 1, demonstrating maximum improvement measurable on the MT score. None of the 9 control subjects followed was able to pass MT at 1 lux at year 1.

In a corresponding finding in the first secondary efficacy endpoint, full-field light sensitivity threshold testing (FST) for white light, intervention subjects demonstrated a highly statistically significant mean improvement of -2.06 log10 (candela second/m2) compared with a decline of 0.04 log10 (candela second/m2) among control subjects (all analyses in mITT population).

A novel mouse model developed by researchers at the National Eye Institute (NEI, Washington, D.C.) found gene therapy can be used to improve visual function in Leber hereditary optic neuropathy (LHON), the NEI said. LHON is tied to gene mutations that damage mitochondria, the group said. 

John Guy, MD, Miami, and fellow researchers used adeno-associated virus to create a mouse model that replicates LHON and an investigational gene therapy for LHON that is currently in clinical trials. To create a mouse model for LHON, the researchers loaded the virus with a defective copy of the ND4 gene carrying the same mutation that causes about 70% of LHON cases. They also included DNA coding for a red fluorescent protein, as a visible marker for the virus and its payload. Then they injected the virus into fertilized mouse egg cells, and grew the cells to maturity. 

To develop a gene therapy for LHON, the team packaged normal human ND4 gene into the same stealthy virus. This combination, when injected into the eye, led to improved visual function in the LHON mouse model. When injected into normal mice, the virus carrying ND4 did not cause any adverse effects on vision.