Overland ADCT BioPharma Announces First Patient Dosed in China with ZYNLONTA® in Pivotal Phase 2 Clinical Trial for Diffuse Large B-cell Lymphoma

BOSTON & SHANGHAI & LAUSANNE, Switzerland–Overland ADCT BioPharma, a joint venture created by Overland Pharmaceuticals and ADC Therapeutics SA (NYSE: ADCT), today announced the first patient has been dosed with ZYNLONTA® in a pivotal Phase 2 clinical trial in patients with relapsed or refractory (r/r) diffuse large B-cell lymphoma (DLBCL) in China. In April 2021, ZYNLONTA was granted accelerated approval by the U.S. Food and Drug Administration (FDA) as the first and only CD19-targeted antibody drug conjugate (ADC) as a single-agent treatment for adult patients with r/r DLBCL after two or more lines of systemic therapy. This local pivotal study mirrors ADC Therapeutics’ ongoing global pivotal Phase 2 clinical trial of ZYNLONTA and its results are intended to support the potential registration of ZYNLONTA in China.

“After receiving early FDA approval of ZYNLONTA in April, we are pleased that our colleagues at Overland ADCT BioPharma have rapidly initiated a pivotal study to potentially benefit patients in China,” said Chris Martin, PhD, Chief Executive Officer of ADC Therapeutics. “We are eager for this bridging study to be completed, and we hope that ZYNLONTA will ultimately be available to all patients who can benefit from it globally.”

“Dosing the first patient in this pivotal trial is a key milestone for Overland ADCT BioPharma as we collaborate to expand the clinical reach of ZYNLONTA in greater China and Singapore,” said Eric Koo, Chief Executive Officer of Overland ADCT BioPharma. “With many patients in China affected by r/r DLBCL, we remain committed to addressing this unmet medical need and delivering promising antibody drug conjugates for underserved patients around the world. Together with ADC Therapeutics, we look forward to the continued development and commercialization of ZYNLONTA in Asia.”

ZYNLONTA, Overland ADCT BioPharma’s lead product candidate, is an ADC composed of a humanized monoclonal antibody directed against human CD19 and conjugated to a pyrrolobenzodiazepine (PBD) dimer cytotoxin. In clinical trials, ZYNLONTA has demonstrated significant single-agent clinical activity across a broad population of patients with r/r DLBCL, mantle cell, and follicular lymphomas.

The China Phase 2, multi-center, open-label, single-arm study will evaluate the efficacy and safety of ZYNLONTA used as monotherapy in patients with r/r DLBCL.

About ZYNLONTA® (loncastuximab tesirine-lpyl)
ZYNLONTA® is a CD19-directed antibody drug conjugate (ADC). Once bound to a CD19-expressing cell, ZYNLONTA is internalized by the cell, where enzymes release a pyrrolobenzodiazepine (PBD) payload. The potent payload binds to DNA minor groove with little distortion, remaining less visible to DNA repair mechanisms. This ultimately results in cell cycle arrest and tumor cell death.

The U.S. Food and Drug Administration (FDA) has approved ZYNLONTA (loncastuximab tesirine-lpyl) for the treatment of adult patients with relapsed or refractory (r/r) large B-cell lymphoma after two or more lines of systemic therapy, including diffuse large B-cell lymphoma (DLBCL) not otherwise specified (NOS), DLBCL arising from low-grade lymphoma and also high-grade B-cell lymphoma. The trial included a broad spectrum of heavily pre-treated patients (median three prior lines of therapy) with difficult-to-treat disease, including patients who did not respond to first-line therapy, patients refractory to all prior lines of therapy, patients with double/triple hit genetics and patients who had stem cell transplant and CAR-T therapy prior to their treatment with ZYNLONTA. This indication is approved by the FDA under accelerated approval based on overall response rate and continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

ZYNLONTA is also being evaluated as a therapeutic option in combination studies in other B-cell malignancies and earlier lines of therapy.

About Overland ADCT BioPharma
Overland ADCT BioPharma, a joint venture created by Overland Pharmaceuticals and ADC Therapeutics, is developing and commercializing four of ADC Therapeutics’ antibody drug conjugate (ADC) product candidates for difficult-to-treat hematologic and solid tumors – ZYNLONTA, ADCT-601, ADCT-602 and ADCT-901 – in greater China and Singapore.

About ADC Therapeutics
ADC Therapeutics (NYSE: ADCT) is a commercial-stage biotechnology company improving the lives of cancer patients with its next-generation, targeted antibody drug conjugates (ADCs). The Company is advancing its proprietary PBD-based ADC technology to transform the treatment paradigm for patients with hematologic malignancies and solid tumors.

ADC Therapeutics is based in Lausanne (Biopôle), Switzerland and has operations in London, the San Francisco Bay Area and New Jersey. For more information, please visit https://adctherapeutics.com/ and follow the Company on Twitter and LinkedIn.

ZYNLONTA® is a registered trademark of ADC Therapeutics SA.

About Overland Pharmaceuticals
Overland Pharmaceuticals is building a fully integrated biopharma company with a mission to bring innovative medicines to underserved patients in Asia and around the world. By leveraging its resources, global network, and local expertise across the biopharma ecosystem in Asia, Overland is establishing a portfolio of differentiated therapeutic candidates in a few carefully selected therapeutic areas. Through formative partnerships, Overland will move forward the development and commercialization of the most promising advances in medicine. www.overlandpharma.com

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Contacts
Overland ADCT BioPharma
Arkin Feng
arkin.feng@rfcomms.com
+86 15626068334

Overland Pharmaceuticals
Kari Watson or Madeline Davidshofer
MacDougall
kwatson@macbiocom.com or mdavidshofer@macbiocom.com
+1 781-235-3060

ADC Therapeutics
Investors
Eugenia Litz
ADC Therapeutics
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Tel.: +44 7879 627205

Amanda Hamilton
ADC Therapeutics
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Tel.: +1 917 288 7023

EU Media
Alexandre Müller
Dynamics Group
amu@dynamicsgroup.ch
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USA Media
Mary Ann Ondish
ADC Therapeutics
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