ESBA105 Penetrates all Segments of the Eye via Topical Eye Drops

ZURICH, Switzerland | April 24, 2008 | ESBATech AG, a leading developer of antibody fragment therapeutics, today announced the initiation of Phase I clinical development of the company’s lead product development candidate, ESBA105, in ophthalmology. This Phase I study is designed to evaluate the safety, tolerability and pharmacokinetic profile of ESBA105, when delivered topically via eye drops in healthy volunteers. The study is being conducted as a single and repeated dose escalation study in Switzerland. ESBA105 is a single-chain antibody fragment directed against TNFa. It is being developed initially for ophthalmic indications.

In previously reported in vivo, preclinical studies, ESBA105 achieved high therapeutic concentrations in all ocular tissues, when delivered topically via eye drops. Therapeutic concentrations of ESBA105 were observed throughout the anterior (front) and the posterior (back) segments of the eye, the latter including the vitreous humor, retina and choroid.

Peter Lichtlen, M.D., Ph.D., Head of Clinical Development at ESBATech AG, commented, "ESBA105 shows an entirely novel and unique intraocular distribution pattern upon topical administration to the eye. Therapeutic levels are reached in both the aqueous and vitreous humor after only a couple of hours following initiation of treatment. Our in vivo, preclinical studies have shown that ESBA105 has a prolonged half-life of 25 hours in the vitreous. Thus, the vitreous acts as a natural depot compartment for ESBA105, allowing for highly attractive maintenance dosing regimens. TNFa is a rapidly emerging target in ophthalmology and ESBA105 has the potential to be a significant advancement in anti-inflammatory ophthalmic medicine."

Dominik Escher, Ph.D., Chief Executive Officer of ESBATech AG, added, "This is a major corporate milestone for ESBATech. After having developed a repeatable technology platform for therapeutic antibody fragments, we started preclinical development of ESBA105 in mid 2006. Now to move this swiftly into the clinic is a truly exciting time for the company. ESBA105 represents a new generation of antibody fragment therapeutics that have favourable biochemical properties over earlier classes of antibody fragments, such as high stability, solubility and high monomeric content. This allows us to deliver the drug topically, without any need to stabilize or modify the protein. Thanks to the small protein size as compared to conventional antibodies, ESBA105 efficiently penetrates into all segments of the eye, which results in a high local concentration where the drug is needed to inhibit inflammation. As this is associated with low systemic drug exposure, this novel therapeutic approach has a very low risk of provoking systemic adverse effects."

ESBATech is the first and only company to date that has successfully screened and characterized the entire human pool (1.5 million) of naturally occurring variable immunoglobulin (VH and VL) domains to select highly stable, soluble and monomeric single-chain antibody fragments frameworks. The company is advancing a pipeline of novel, antibody fragment therapeutics for topical and/or local delivery, to ensure safe and convenient patient therapy.

About ESBATech AG

ESBATech AG is a Zurich, Switzerland-based, privately held drug discovery and development company focused on advancing antibody fragments for therapeutic applications. The company applies its proprietary, fully human single-chain antibody frameworks to generate product candidates against targets of clinical relevance. ESBATech is focused on delivering high concentrations of its therapeutic antibody fragments to the targeted sites, in combination with extremely low systemic load, in order to achieve low risk of systemic drug reactions using topical and local delivery. Current venture investors include SV Life Sciences, Clarus Ventures, HBM BioVentures, HBM BioCapital, Novartis Venture Fund, BioMedinvest and VI Partners. For more information about ESBATech, please visit, http://www.esbatech.com.

SOURCE: ESBATech AG