Seagen to Highlight Two Novel Antibody-Drug Conjugates (ADCs) at the SITC 36th Annual Meeting

Rhea-AI Summary

Seagen announced the advancement of two new antibody-drug conjugate (ADC) programs, SGN-PDL1V and SGN-B7H4V, into Phase 1 studies, boosting its pipeline to 10 ADCs. These ADCs target immune checkpoints with preclinical data showing promising antitumor activity. SGN-PDL1V targets PD-(L)1, exhibiting strong activity in xenograft models, while SGN-B7H4V targets B7-H4, showing effectiveness in various solid tumors. Both ADCs are set for first-in-human studies in 2022, as presented at the Society for Immunotherapy of Cancer Annual Meeting.

Positive

• Advancement of SGN-PDL1V and SGN-B7H4V into Phase 1 studies strengthens the clinical pipeline.
• Both programs demonstrate promising preclinical antitumor activity, indicating potential efficacy.

Negative

• Forward-looking statements indicate risks related to the efficacy and safety of new treatments.
• Uncertainties in drug development could impact the anticipated timelines and outcomes.

--Data Support Advancing SGN-PDL1V and SGN-B7H4V into Phase 1 Studies, Increasing Robust Pipeline to 10 ADC Programs--

--Leverages Seagen’s Leadership in ADC Technology--

BOTHELL, Wash.--(BUSINESS WIRE)-- Seagen Inc. (Nasdaq:SGEN), today announced the presentation of two new vedotin-based antibody-drug conjugate (ADC) programs at the Society for Immunotherapy of Cancer (SITC) 36th Anniversary Annual Meeting, taking place in Washington, D.C. and virtually, November 10-14, 2021. Each program combines antibodies targeted to an immune checkpoint [PD-(L)1 or B7-H4] with the cytotoxic properties of the vedotin payload. Preclinical data demonstrate promising antitumor activity. Both ADCs are set to enter first-in-human phase 1 studies in 2022.

“We are excited to advance two novel immune checkpoint vedotin ADCs, SGN-PDL1V and SGN-B7H4V, into phase 1 studies. These programs utilize a clinically validated payload and have the potential to be first in class ADCs,” said Roger Dansey, M.D., Chief Medical Officer at Seagen.

SGN-PDL1V is a novel, investigational vedotin ADC directed to the T cell checkpoint ligand, PD-(L)1. PD-(L)1 is a target with limited normal tissue expression and clinically validated expression across a variety of malignancies, including non-small cell lung cancer (NSCLC) and head and neck squamous cell carcinomas (HNSCC). SGN-PDL1V is engineered for efficient delivery of the therapeutic payload, monomethyl auristatin E (MMAE), and is proposed to have distinct mechanisms of action from other PD-(L)1-directed therapeutics, including direct cytotoxicity against PD-(L)1-expressing cells, bystander killing, and immunogenic cell death. SGN-PDL1V demonstrates robust antitumor activity in xenograft models, including in tumors with low, heterogenous PD-(L)1 expression, supporting the potential to treat patients across a wide range of PD-(L)1 expression levels. (Abstract #783)

SGN-B7H4V is a novel, investigational vedotin ADC directed to the T cell checkpoint ligand, B7-H4. B7-H4 expression is limited on normal tissue and overexpressed on a variety of solid malignancies, including breast, ovarian, and endometrial tumors. SGN-B7H4V is designed to bind and internalize the B7-H4/ADC complex from the surface of the tumor cells and release the therapeutic payload MMAE, inducing MMAE-mediated direct cytotoxicity, bystander killing, and immunogenic cell death, as well as antibody-dependent cellular cytoxicity (ADCC) and phagocytosis (ADCP). SGN-B7H4V demonstrates strong activity in xenograft models, including models with heterogenous B7-H4 expression. (Abstract #854)

The abstracts published in advance of the SITC Annual Meeting can be found here. All data presentations will be available on-demand starting on November 9.

Details of Seagen Presentations at SITC Annual Meeting 2021:

Abstract Title	Abstract #	Presentation	Presenter
SGN-PDL1V, a novel, investigational PD-L1- directed antibody-drug conjugate for the treatment of solid tumors	#783	Poster November 12–13 7:00 a.m. – 8:30 p.m.	Dr. Byron Kwan
SGN-B7H4V, a novel, investigational vedotin antibody-drug conjugate directed to the T cell checkpoint ligand B7-H4, shows promising activity in preclinical models	#854	Poster November 12–14 7:00 a.m. – 5:00 p.m.	Dr. Elizabeth Gray
Phase 1 study of SEA-TGT, a human, nonfucosylated anti-TIGIT monoclonal antibody with enhanced immune-effector function, in patients with advanced malignancies (SGNTGT-001, trial in progress)	#474	Poster November 12–14 7:00 a.m. – 5:00 p.m.	Dr. Diwakar Davar

About Seagen

Seagen is a global biotechnology company that discovers, develops and commercializes transformative cancer medicines to make a meaningful difference in people’s lives. Seagen is headquartered in the Seattle, Washington area, and has locations in California, Canada, Switzerland and the European Union. For more information on the company’s marketed products and robust pipeline, visit www.seagen.com and follow @SeagenGlobal on Twitter.

Forward-Looking Statements

Certain of the statements made in this press release are forward-looking, such as those, among others, relating to the therapeutic potential of SGN-PDL1V, SGN B7H4V and SEA-TGT, their possible safety, efficacy and therapeutic uses, anticipated development activities including clinical trial activities, and the company’s pipeline. Actual results or developments may differ materially from those projected or implied in these forward-looking statements. Factors that may cause such a difference include the difficulty and uncertainty of pharmaceutical product development, the risk of adverse events or safety signals, the inability to show sufficient activity in clinical trials and the possibility of adverse regulatory actions. More information about the risks and uncertainties faced by Seagen is contained under the caption “Risk Factors” included in the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2021, filed with the Securities and Exchange Commission. Seagen disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

View source version on businesswire.com: https://www.businesswire.com/news/home/20211109006061/en/

For Media:

David Caouette

Vice President, Corporate Communications

(310) 430-3476

dcaouette@seagen.com

For Investors:

Peggy Pinkston

Senior Vice President, Investor Relations

(425) 527-4160

ppinkston@seagen.com

Source: Seagen Inc.

FAQ

What are SGN-PDL1V and SGN-B7H4V?

SGN-PDL1V and SGN-B7H4V are new investigational ADCs by Seagen targeting immune checkpoints PD-(L)1 and B7-H4, respectively.

When will SGN-PDL1V and SGN-B7H4V enter clinical studies?

Both SGN-PDL1V and SGN-B7H4V are set to enter Phase 1 studies in 2022.

Where was the announcement about SGN-PDL1V and SGN-B7H4V made?

The announcement was made at the Society for Immunotherapy of Cancer (SITC) Annual Meeting in November 2021.

What is the significance of these new ADC programs for Seagen?

Advancing these ADCs enhances Seagen's pipeline and potential market position in oncology treatments.

What are the potential risks mentioned for SGN-PDL1V and SGN-B7H4V?

Risks include the uncertainty of clinical trial outcomes and potential adverse events affecting safety and efficacy.