Aptevo Therapeutics Announces Plans to Conduct Phase 2 Study

Aptevo Therapeutics Inc. recently announced recent developments related to the Company’s novel ADAPTIR bispecific antibody platform, including the planned commencement of a Phase 2 clinical evaluation of its monospecific antibody candidate, otlertuzumab, in a new indication – peripheral T-cell lymphoma (PTCL), scheduled to begin in the fourth quarter of 2017.

In addition, Aptevo announced that the Company expects to file two Investigational New Drug (IND) applications in 2018 for two bispecific antibody candidates, APVO436, being developed for the treatment of acute myeloid leukemia (AML), and APVO210, being developed for the treatment of autoimmune and inflammatory diseases.

“We continue to make solid progress advancing our ADAPTIR portfolio with the expansion of our otlertuzumab clinical development program to include a new indication in PTCL, as well as planned IND filings for two new ADAPTIR candidates in 2018,” said Scott Stromatt, Chief Medical Officer. “Recently, intriguing evidence has been reported on the overexpression of CD37 on T-cell malignancies, suggesting a potential role for otlertuzumab in an attractive, orphan drug-eligible indication with high unmet medical need. Based on these developments, Aptevo has decided to expand its existing Phase 2 clinical protocol to evaluate otlertuzumab in PTCL and discontinue enrollment in the ongoing cohorts evaluating otlertuzumab in CLL with the intention of continuing to explore partnership opportunities for Phase 3 development of otlertuzumab in CLL. With clinical proof-of-concept data demonstrating the efficacy and tolerability of otlertuzumab in previous combination studies, we believe that evidence of a clinical effect in PTCL could open up a promising new market opportunity for otlertuzumab in the treatment of T-cell malignancies where there is a significant need for safe and effective new treatments.”

“Aptevo is quickly establishing an impressive portfolio of novel immunotherapeutics with a number of candidates advancing, or poised to advance, into the clinic over the next 12 to18 months,” continued Dr. Stromatt. “We believe that bispecifics represent the next frontier in antibody therapeutics and are encouraged by Aptevo’s rapid progress in this field. Importantly, the enhancements we have made to our next generation ADAPTIR platform are differentiated from other bispecific platforms, allowing us to assemble bispecific molecules that possess desired antibody-like features, including efficient manufacturing properties, extended half-life, improved potency, increased stability, and the potential for reduced toxicity. We look forward to data read-outs next year from our current clinical candidates, APVO414 and otlertuzumab, and to further expanding our portfolio of clinical candidates.”

The Phase 2 study is an open-label, proof-of-concept evaluation of the safety and efficacy of otlertuzumab in combination with bendamustine in patients with relapsed or refractory peripheral T-cell lymphomas (PTCL). Up to 24 patients will be enrolled in the study. The primary endpoint is response rate, evaluable by the 2017 International Working Group consensus response evaluation criteria in lymphoma (RECIL 2017).

Otlertuzumab is a monospecific antibody targeting CD37 that was built on Aptevo’s ADAPTIR modular protein therapeutic platform. CD37 is a member of the tetraspanin superfamily of molecules and is expressed on the surface of normal and transformed B cells, and also recently discovered to be present on the surface of T-cell lymphomas.

According to the Lymphoma Research Foundation, peripheral T-cell lymphoma (PTCL) consists of a group of rare and typically aggressive Non-Hodgkin lymphomas (NHLs) that develop from mature T-cells. Most T-cell lymphomas (a type of blood cancer) are classified as PTCLs. Treatment options for relapsed and refractory PTCL are limited, with only two approved drugs on the market, FOLOTYN and ISTODAX, with worldwide sales of approximately $50 million and $80 million, respectively.

Aptevo Therapeutics Inc. is a clinical-stage biotechnology company focused on novel oncology and hematology therapeutics to meaningfully improve patients’ lives. Aptevo has a commercial product, IXINITY coagulation factor IX (recombinant), approved and marketed in the US for the treatment of Hemophilia B, and a versatile core technology – the ADAPTIR modular protein technology platform capable of generating highly differentiated bispecific antibodies with unique mechanisms of action to treat cancer and autoimmune diseases. Aptevo has two ADAPTIR antibody candidates currently in clinical development and a broad pipeline of novel investigational-stage bispecific antibody candidates focused in immuno-oncology and autoimmune disease and inflammation. For more information, visit www.aptevotherapeutics.com.