ADC Therapeutics Announces the Termination of its ADCT-502 Program Targeting HER2 Expressing Solid Tumors

Data on safety, tolerability, pharmacokinetics and efficacy did not demonstrate sufficient patient benefit to justify further development

LAUSANNE, Switzerland--()--ADC Therapeutics (ADCT), an oncology drug discovery and development company that specializes in the development of proprietary Antibody Drug Conjugates (ADCs) targeting major cancers, today announced that it has terminated the Phase I clinical trial to evaluate its antibody drug conjugate (ADC) ADCT-502 in patients with advanced solid tumors with HER2 expression.

Dr. Jay Feingold, Chief Medical Officer and Senior Vice President of Clinical Development at ADCT said: "We are very pleased with the efficacy and tolerability achieved with our lead hematological PBD-based ADC programs, but regrettably this has not been the case with our HER2 targeted ADC. PBD's (pyrrolobenzodiazepine dimers) are extremely potent and have a well characterized safety profile that includes fluid retention and pulmonary edema. For most PBD ADCs this can be managed by selecting dosing regimens that are efficacious with manageable toxicities. However, during dose escalation in this trial we did not achieve the necessary efficacy at tolerated doses required for patient benefit. This was possibly due to the extensive expression of HER2 in pulmonary tissue. Our next two solid tumor ADCs progressing into the clinic over the next nine months incorporate site specific conjugation technology which based on pre-clinical models has the potential to substantially improve tolerability and efficacy in difficult to treat solid tumors. Preclinical data on these programs was presented at the recent American Association of Cancer Research conference."

Chris Martin, CEO at ADCT said: "Patients with HER2 expressing tumors have multiple therapeutic options including novel therapies in clinical development that are producing encouraging data. ADC Therapeutic's strategy is to progress a deep pipeline of ADCs into Phase I in order to assess their clinical and market potential based on actual human data, and only to progress into later stage development those ADCs that demonstrate the potential to be best in class in areas of high unmet medical need. We currently have three other ADC programs in the clinic, and we plan to commence clinical trials for three additional programs in the next 9 months, including a third hematological program. Moreover, our two most advanced clinical programs are progressing into later stage development over 2018."

At this time, ADC Therapeutics is collecting and evaluating the study data from the ADCT-502 Phase I trial, which will be presented for publication later this year.

About ADCT-502
ADCT-502 is an investigational antibody drug conjugate (ADC) composed of the humanized monoclonal antibody trastuzumab directed against the human epidermal growth factor receptor 2 (HER2). The antibody is site-specifically conjugated to the PBD-based linker-drug tesirine. Once bound to the HER2 receptor on the cell surface, ADCT-502 is internalized into the cell where enzymes release the PBD-based warhead. HER2 is a well-established, clinically validated target expressed in a wide variety of solid tumors, including breast, gastric, esophageal, bladder and lung cancer.

About ADC Therapeutics
ADC Therapeutics SA (ADCT) is an oncology drug discovery and development company that specializes in the development of proprietary antibody drug conjugates (ADCs) targeting major hematological malignancies and solid tumors. The Company's ADCs are highly targeted biopharmaceutical drugs that combine monoclonal antibodies specific to surface antigens present on particular tumor cells with a novel class of highly potent pyrrolobenzodiazepine (PBD) based warheads via a chemical linker. The Company has multiple PBD-based antibody drug conjugates in ongoing clinical trials in the USA and Europe, and a deep pipeline of other preclinical ADCs in development. ADCT enjoys strong relationships with world class partners, including AstraZeneca and its global biologics research and development arm, MedImmune. The Company is based in Lausanne (Biopôle), Switzerland and has operations in London, San Francisco and New Jersey. (www.adctherapeutics.com).

Additional features:

Document: http://n.eqs.com/c/fncls.ssp?u=QMKPNYVMYB
Document title: ADCT_PR_502_25.04.2018

Contacts

For more information please contact:
Dr. Chris Martin Chief Executive Officer
chris.martin@adctherapeutics.com
Tel.: +41 (0) 21 653 0200
or
Alexandre Müller
Dynamics Group
amu@dynamicsgroup.ch
Tel: +41 (0) 43 268 3231