Aqueous humour concentration of topically applied 2.0% ganciclovir eye drops in eyes with cytomegalovirus anterior uveitis and endotheliitis.

Background: To investigate the level of ganciclovir in the aqueous humour (AH) following topical application of 2.0% ganciclovir eye drop in eyes with cytomegalovirus (CMV) anterior segment infection.

Methods: This is a prospective, non-randomised, interventional clinical study. We enrolled patients with active CMV anterior segment infection. Patients were treated with 2.0% ganciclovir eye drop, which was administered one drop every 3 h for 6 weeks. At the end of week 6, the CMV viral load in the AH was measured using real time polymerase chain reaction and the ganciclovir concentration in the AH was measured using high-performance liquid chromatography-mass spectrometry. The clinical activity and central corneal thickness (CCT) were recorded at baseline and post-treatment.

Results: Of the 25 eyes of 25 patients studied, 21 had anterior uveitis and 4 had endotheliitis. After 6 weeks of treatment, 22 eyes did not have any inflammation in the anterior chamber (AC) and CMV was undetectable on real time PCR. Three eyes of non-compliant patients responded partially with reduced AC inflammation and decreased CMV viral load in the AH. The mean ganciclovir concentration in the AH was 1252.88 ± 2408.82 ng/mL. There was no significant correlation between the ganciclovir concentration in the AH and the CCT (Spearmen's r = +0.19, p = 0.36).

Conclusions: Three-hourly application of 2.0% ganciclovir eye drops resulted in effective intra-cameral penetration with drug concentrations in the AH exceeding the 50% inhibitory dose for CMV replication. The ocular penetration of the ganciclovir eye drop was not dependent on corneal thickness.