Press Releases « back

Inhibrx Announces Dosing of First Patients in Phase 1 Dose-Escalation Study of INBRX-109, a Novel Multivalent Agonist of Death Receptor 5 (DR5)

-Interim data expected in 1H 2019-

San Diego, CA December 6, 2018 – Inhibrx, Inc. (Inhibrx), a clinical-stage biotechnology company with a broad pipeline of biotherapeutics in development, announced today the administration of the first dose of INBRX-109 in a Phase 1 dose-escalation clinical study. INBRX-109 is a novel, multivalent agonist of death receptor 5 (DR5) in development for the treatment of solid tumors, including sarcomas. The ongoing clinical study aims to determine the safety of INBRX-109 in humans, as well as the recommended therapeutic dose level for future clinical development.

“DR5 has a long history as a promising target for cancer therapy because of its ability to selectively induce apoptosis in cancer cells,” said Mark Lappe, CEO of Inhibrx. “INBRX-109 was designed to overcome the limitations of previously explored DR5 targeting approaches and we are excited to have achieved our first dose in cancer patients.”

“This is the first therapeutic candidate built using our proprietary single domain antibody platform to enter clinical development, and we believe this is a great example of the functionally optimized therapeutic candidates that can be crafted with this flexible technology,” said Brendan Eckelman, CSO and EVP, Corporate Strategy of Inhibrx.

About INBRX-109

INBRX-109 is a multivalent agonist of death receptor 5 (DR5). It was built with the proprietary Inhibrx single domain antibody platform (sdAb). Agonism of the DR5 receptor is mediated by receptor clustering and initiates signaling that leads to tumor cell apoptosis, or programmed cell death. Able to bind four receptors with a single drug molecule, INBRX-109 has been shown in preclinical studies to efficiently cluster cell surface DR5 molecules in close proximity to induce efficient apoptotic signaling and tumor cell death. Additionally, the single-domain antibodies within INBRX-109 were engineered to avoid recognition by antibodies that can pre-exist in human serum, obviating a potential liability of single domain antibodies. Inhibrx expects to report interim dose-escalation data, which will inform future clinical development plans for INBRX-109 in the first half of 2019.

About the Inhibrx sdAb Platform

Inhibrx utilizes diverse methods of protein engineering in the construction of therapeutic candidates that can address the specific requirements of complex target and disease biology. A key tool for this effort is the Inhibrx proprietary sdAb platform, which enables the development of therapeutic candidates with attributes superior to other monoclonal antibody and fusion protein approaches. This platform allows the combination of multiple binding units in a single molecule, enabling the creation of therapeutic candidates with defined valency or multiple specificities, potentially capable of enhanced cell signaling or conditional activation. An additional benefit of this platform, these optimized, multi-functional entities can be manufactured using the established processes that are commonly used to produce therapeutic proteins.

Initially, Inhibrx is pursuing targets with early clinical validation, such as DR5, where other therapeutics have demonstrated liabilities. In addition, Inhibrx is developing a portfolio of sdAb based therapeutic candidates in a variety of indications for both known and novel targets.

About Inhibrx Inc.

Inhibrx is a clinical-stage biotechnology company focused on developing a broad pipeline of biologic therapeutic candidates. Inhibrx utilizes diverse methods of protein engineering to therapeutically address the specific requirements of complex target and disease biology, including its proprietary sdAb platform. The Inhibrx pipeline is focused on oncology, infectious disease and orphan diseases. Inhibrx has collaborations with Celgene and the Alpha-1 Foundation and has received awards from several granting agencies, including NIH, NIAID and CARB-X. For more information, please visit

Forward Looking Statements

Certain statements in this press release are forward looking statements that involve a number of risks and uncertainties. These statements include statements about Inhibrx’s strategy, therapeutic candidates, sdAb platform and preclinical and clinical programs. These statements represent Inhibrx’s judgements and expectations as of the date of this release. Actual results may differ due to a number of factors, including, but not limited to, the potential success and efficacy of Inhibrx’s therapeutic candidates, the timing and success of its clinical studies, the timing of receipt of fees and payments, if any, from Inhibrx’s collaborators and its ability to obtain funding as needed to support its operations. Inhibrx disclaims any intent or obligation to update these forward looking statements, other than as may be required by applicable law.

Investor and Media Contact:

Amy Conrad
Juniper Point