Abdera Therapeutics Announces FDA Orphan Drug Designation for ABD-147 for the Treatment of Neuroendocrine Carcinoma

SOUTH SAN FRANCISCO, CA, September 5, 2024 – Abdera Therapeutics Inc., a biopharmaceutical company leveraging its advanced antibody engineering ROVEr™ platform to design and develop tunable, precision radiopharmaceuticals for cancer, today announced that the U.S. Food and Drug Administration (FDA) has granted Orphan Drug Designation to ABD-147 for the treatment of neuroendocrine carcinoma. ABD-147 is a next-generation precision radiopharmaceutical biologic therapy designed to deliver Actinium-225 (225Ac) to solid tumors expressing DLL3, a protein found on the surface of neuroendocrine tumors, but rarely expressed on the surface of normal cells or tissues. In 2024, Abdera plans to initiate a first-in-human Phase 1 clinical trial with ABD-147 in patients with small cell lung cancer (SCLC) or large cell neuroendocrine carcinoma (LCNEC) who previously received platinum-based therapy.

“Neuroendocrine carcinomas, including SCLC and LCNEC, are aggressive and challenging to treat effectively with current systemic therapies,” said Philippe Bishop, M.D., chief medical officer. “By delivering a potent radioisotope to neuroendocrine tumors expressing DLL3 with custom-engineered PK properties, we believe ABD-147 has the potential to become a best-in-class DLL3-targeting treatment for aggressive neuroendocrine tumors. Along with FDA recently granting Fast Track designation to ABD-147 for the treatment of patients with extensive stage small cell lung cancer (ES-SCLC) who have progressed on or after platinum-based chemotherapy, this Orphan Drug Designation for neuroendocrine carcinoma further underscores the potential of ABD 147 development to offer a significant advantage beyond approved drugs.”

The FDA’s Orphan Drug Designation program provides orphan status to drugs and biologics for rare diseases that meet certain criteria. Orphan Drug Designation provides various incentives including tax credits for qualified clinical trials, exemption from user fees, and the potential for seven years of market exclusivity after approval.

About Neuroendocrine Carcinoma

Neuroendocrine carcinoma is a type of cancer that originates from neuroendocrine cells, which have characteristics of both nerve cells and hormone-producing cells. These cancers can develop in various parts of the body, including the lungs (SCLC and LCNEC), the digestive tract, pancreas, prostate, and other endocrine glands and share similar clinical and pathologic traits characterized by higher mitotic rates with extensive necrosis, high tumor mutational burden, and neuroendocrine gene expression.

About Small Cell Lung Cancer and Large Cell Neuroendocrine Carcinoma

The global incidence for SCLC and LCNEC has been reported to represent approximately 325,000 patients and is expected to increase 4% annually through 2029. In the U.S., the incidence has been reported to be approximately 35,000 new cases annually. Fifteen percent of all lung cancer cases are high-grade neuroendocrine cancers. These cancers have the most aggressive clinical course of any type

of pulmonary tumor and often metastasize to other parts of the body, including the brain, liver and bone. Without treatment, the median survival from diagnosis has been reported to be only two to four months. With treatment, the overall survival at five years is 5% to 10% for SCLC, and 15% to 25% for LCNEC. SCLC and LCNEC generally carry a poor prognosis and new treatment options are urgently needed.

About ABD-147

ABD-147 is a targeted radiopharmaceutical biologic therapy designed to deliver Actinium-225 (225Ac), a highly potent alpha-emitting radioisotope, to solid tumors expressing delta-like ligand 3 (DLL3) with high affinity. DLL3 is a protein in the Notch pathway that is critical for the development and regulation of neuroendocrine versus epithelial cell differentiation in the lungs. In certain high grade neuroendocrine carcinomas including small cell lung cancer (SCLC), DLL3 is upregulated and specifically expressed on the cell surface in more than 80% of cases. In contrast, DLL3 is absent or very rarely expressed on the surface of nonmalignant cells. Given the high specificity of DLL3 expression on cancer cells and the distinct mechanism of action, DLL3 represents a compelling target for treating SCLC and other DLL3+ solid tumors with targeted radiotherapy.

About the ROVEr™ Platform

Abdera’s Radio Optimized Vector Engineering (ROVEr™) platform enables the company to custom-engineer targeted radiopharmaceuticals with tunable pharmacokinetic (PK) properties to achieve high tumor uptake while minimizing renal exposure and mitigating other systemic radiotoxicities such as myelosuppression. Abdera can optimize the delivery and therapeutic index of potent radioisotopes capable of emitting powerful alpha or beta particles to selectively destroy tumor cells while sparing healthy cells, providing patients with potentially transformative new cancer treatments.

Abdera’s approach offers the ability to design radiotherapeutics against virtually any cancer target expressed on the cell surface. Coupled with a highly potent mechanism of cell killing, the ROVEr platform is uniquely poised to exploit both high- and low-expressing targets to selectively deliver therapeutic levels of radioisotope to cancer cells.

About Abdera

Abdera Therapeutics is a biopharmaceutical company leveraging antibody engineering to design and develop new precision radiopharmaceuticals for cancer. Abdera’s Radio Optimized Vector Engineering (ROVEr™) platform enables the company to engineer potential best-in-class therapies for both clinically validated and novel targets that deliver potent radioisotopes capable of emitting alpha or beta particles to selectively destroy cancer cells. Abdera’s lead program, ABD-147, is a next-generation precision radiopharmaceutical biologic therapy designed to deliver Actinium-225 (225Ac) to solid tumors expressing delta-like ligand 3 (DLL3) for the treatment of small cell lung cancer (SCLC) and large cell neuroendocrine carcinoma (LCNEC). Headquartered in South San Francisco, CA, Abdera also has offices in Vancouver, British Columbia, Canada. To learn more, please visit www.abderatx.com and follow us on LinkedIn and X.

Contacts:

Media:
1AB
Katie Engleman
katie@1abmedia.com

Investors:
1AB
Steve Klass
Steve@1abmedia.com

Read the press release here.