Celtic Therapeutics invests $50M in developing antibody drug conjugates

30 April 2012

Celtic Therapeutics Management LLLP, a global private equity firm, has announced a significant commitment to antibody drug conjugate products, with the launch of a new Switzerland-based company.

ADC Therapeutics has been formed with a pipeline of ten proprietary ADC oncology development programs, targeting multiple major cancers, including prostate, renal, breast, lung and blood cancers and an initial budget of US$50million.

ADCs are fast becoming the most exciting new class of oncology drugs, as they combine the specificity of antibodies with the cytotoxic power of novel “warhead” chemistries. ADCs thus have the prospect of being highly potent and target selective, with fewer side effects, and to potentially minimize drug resistance.

ADC Therapeutics, to be headquartered from Lausanne, Switzerland, will focus on driving its ten initial ADC programs through pre-clinical assessment over the next twelve months and will move the first of these into clinical development within two years. The Company’s strategy will be to seek development and marketing partners after Phase II proof of concept (POC). The objective is to achieve clinical POC in Phase II studies in several programs within three to five years.

Celtic Therapeutics is the majority owner of ADC Therapeutics, alongside certain co-founders of UK-based Spirogen Limited, and is also the majority owner of Spirogen, a platform technology company that is a world leader in cytotoxic “warhead” and linker chemistries for ADCs. UK specialist commercialization and development company Cancer Research Technology Ltd is also a shareholder in ADC Therapeutics.

The board of directors includes Michael Forer, CEO ADC Therapeutics and Partner in Celtic Therapeutics together with Dr. Peter B. Corr and Stephen Evans-Freke, Co-Founders and Managing General Partners of Celtic Therapeutics, and Dr. Christopher Martin, CEO of Spirogen. Celtic Therapeutics has also attracted eminent oncology experts Dr. Samuel Broder and Dr. Barrie Ward as non-executive directors of ADC Therapeutics. Dr. Broder is the former Director of the National Cancer Institute in the USA from 1989-95 and founding member of Celera in 1998. Dr. Ward is the former CEO of oncology company KuDOS Pharmaceuticals prior to its sale to AstraZeneca.

In selecting the ADC programs, Celtic Therapeutics brought together an international panel of scientific advisors, chaired by key opinion leader, Dr. Neil Bander of Weill-Cornell Medical College, USA. This culminated in an initial target list of ten well-validated, cancer-specific cell surface receptor targets (antigens), important in large subsets of many of the most common forms of cancer.

ADC Therapeutics’ development plan for the ADCs will use well-characterized monoclonal antibodies against these ten antigens for conjugation with best-in-class warhead and linker chemistry. The warheads are based on proprietary pyrrolobenzodiazepines (PBDs) “payload” technology developed by Spirogen and scientists at University College, London, over the past 10 years, expertly designed to maintain warhead potency and water solubility when linked to antibodies, and potentially minimize drug resistance.

Through in-house in vitro and in vivo data generated by Spirogen, and in vivo data from six independent industry partners, Spirogen has demonstrated that its PBDs are significantly more efficacious than alternative ADC warhead chemistries in a wide variety of tumour models. Among other partners, it signed a collaboration agreement with Genentech in January 2011.

Dr Peter B Corr, Co-Founder and Managing General Partner of Celtic commented: “ADCs have strong potential to address the global need for markedly better cancer therapies with greater specificity and reduced side effects. Now is the time to move ADCs to center-stage in cancer drug development. In forming ADC Therapeutics we have created a company targeting a broad range of antigens specific to different tumor types that are ideal targets for ADC therapies, coupled with the drug development capabilities to bring ADCs into the clinic rapidly and cost-effectively.”

Stephen Evans-Freke, Co-Founder and Managing General Partner of Celtic Therapeutics added: “We believe that ADCs will represent a significant medical breakthrough in cancer therapy over the coming decade, and that Spirogen’s PBDs constitute ‘best-in-class’ ADC warheads. We anticipate investment of up to $50m into ADC Therapeutics to achieve clinical proof of concept in 2-3 lead oncology programs. We are committed to fully fund ADC Therapeutics and will raise additional capital if warranted.”