HighField Biopharmaceuticals Files INDs for Two ADCplex™ Immunoliposomes with Different Cancer Killing Payloads to Overcome Limitations of Current ADCs

The new technology behind HighField’s immunoliposomes may offer greater safety and efficacy than existing antibody drug conjugates (ADCs)

HighField Biopharmaceuticals, a clinical stage company using lipid-based therapeutics to treat cancer and other diseases, announced today it has filed two investigational new drug (IND) applications (HF158K1 and HFK2) with China’s National Medical Products Administration for immunoliposomes carrying different cancer killing payloads. The planned clinical study will evaluate the two drugs’ safety and pharmacokinetics as well as their combined therapeutic effects in solid tumor patients refractory to prior treatments.

The two drugs are derived from HighField’s proprietary ADCplex^TM platform, containing chemotherapy payloads inhibiting Topoisomerase I and Topoisomerase II activities respectively. HF158K1 (K1) and HFK2 (K2) are both fitted with HER2 antibodies for binding to cancer cell surface HER2 receptors in both HER2 high and low tumors.

K1 is being evaluated as a monotherapy in an ongoing Phase 1 trial in the US (NCT05861895). The planned Phase 1 open label, dose escalation trial of K1 and K2 in China will evaluate the safety and pharmacokinetics of K1 as a monotherapy and preliminary efficacy in combination with K2.

HighField CEO and Scientific Founder Yuhong Xu, Ph.D., explained, “The antibody-drug-conjugate (ADC) drugs are designed based on a great concept. Their specificity and efficacy in cell culture models are always perfect. However, in patients, the process of ADC tumor penetration, especially intracellular payload release inside cancer cells, is profoundly nonlinear. Therefore, increasing the dose may not lead to improved efficacy, but only increased toxicity.”

Dr. Xu observed, “Upon modeling the tumor penetration and intracellular delivery process, we came up with the ‘golf cart’ approach. The liposomes ‘escort’ the payloads in a more efficient way than ADCs so there is a close to linear dose vs. intracellular delivery correlation. In this case, we can even combine two kinds of immunoliposomes carrying two different payloads and expect higher efficacy and low toxicity.”

Preclinical efficacy studies in mouse tumor models showed greater efficacy from K1, K2 and the two combined than marketed ADCs with the same HER2 target. In addition, the efficacy to maximum tolerant dose (MTD) therapeutic windows are wider.

About HighField Biopharmaceuticals

HighField is a clinical stage company focused on novel applications of liposome constructs directed to immuno-oncology and gene therapy. HighField’s lead products in clinical trials are K1, derived from its ADCplex^TM platform, followed by HF50, derived from its TCEplex^TM platform. The company’s pipeline also includes K16, a drug encapsulated immune modulating liposome targeting myeloid-derived suppressor cells in clinical trials for refractory cancers; and HFG1, derived from its tLNPplex™ platform, for mRNA expression of a GLP-1R agonist for weight loss and diabetes. For more information visit https://highfieldbio.com/.

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The new technology behind HighField’s immunoliposomes may offer greater safety and efficacy than existing antibody drug conjugates (ADCs)