FDA Grants Orphan Drug Designation to BDC-1001 in Gastric Cancer

• BDC-1001, an immune-stimulating antibody conjugate (ISAC), is undergoing phase 1/2 trials.¹

• Orphan drug designation (ODD) incentives include tax credits and exemption from user fees.

• If approved, BDC-1001 could obtain 7 years of market exclusivity.

The Food and Drug Administration (FDA) granted ODD to BDC-1001, an ISAC for the treatment of gastric cancer.

“Receiving orphan drug designation from the FDA is an important step forward in the development of BDC-1001 and reinforces the potential of BDC-1001 to address unmet needs for patients with gastric cancers,” said Edith A. Perez, MD, chief medical officer of Bolt Biotherapeutics in a press release.¹

BDC-1001 is in phase 2 development for the treatment of HER2-positive colorectal, endometrial, and gastroesophageal cancers. The phase 2 study (NCT04278144) is evaluating BDC-1001, a biosimilar of trastuzumab (Herceptin) conjugated with a non-cleavable linker to a TLR7/8 agonist, as a single agent and in conjunction with nivolumab (Opdivo), a PD-1 inhibitor.

An estimated 390 patients are enrolled in the trial, which began in February 2020. The estimated study completion date is October 2026. The trial is composed of 4 parts. Part 1 evaluates BDC-1001 as a single agent and determines the maximum-tolerated dose (MTD), recommended phase 2 dose (RP2D), and maximum protocol dose (MPD). Part 3 will apply the selected dose as a monotherapy. Part 2 will evaluate the MTD of BDC-1001 when used with nivolumab, and the selected doses will be administered in Part 4.

The primary outcome measures are incidence of adverse events (AEs), incidence and nature of dose-limiting toxicities (DLTs), incidence of potential immune-related toxicities, MTD, and objective response rate (ORR) or confirmed complete or partial response.

3D-rendered image of stomach | Image Credit: © SciePro - stock.adobe.com

Inclusion criteria for the trial indicates that patients must have an advanced solid tumor with documented HER2-protein expression or gene amplification. Exclusion criteria includes a history of severe hypersensitivity to the study drugs; previous treatment with a TLR 7, TLR 8, or a TLR 7/8 agonist; and impaired cardiac function or history of significant cardiac disease.²

“We look forward to advancing BDC-1001 in clinical development and bringing this novel immunotherapy to patients in need of further treatment options,” Perez said.

A second phase 2 study (NCT05954143) is evaluating BDC-1001 as a single agent and in conjunction with pertuzumab (Perjeta) for HER2-positive breast cancer treatment. The study has an estimated completion date of March 2025.³

REFERENCES

1. Bolt Biotherapeutics receives orphan drug designation for BDC-1001 for treatment of gastric cancers. Bolt Biotherapeutics. September 28, 2023. Accessed October 2, 2023. https://tinyurl.com/ywd6xtuc

2. Bolt Biotherapeutics, Inc. - NCBI. A first-in-human study using BDC-1001 as a single agent and in combination with nivolumab in advanced HER2-expressing solid tumors. National Library of Medicine. September 13, 2023. Accessed October 2, 2023. https://clinicaltrials.gov/study/NCT04278144

3. Bolt Biotherapeutics, Inc. – NCBI. Trial of BDC-1001 +/- pertuzumab in subjects with HER2-positive metastatic breast cancer. National Library of Medicine. September 21, 2023. Accessed October 2, 2023. https://classic.clinicaltrials.gov/ct2/show/NCT05954143