More than two-thirds of newly diagnosed breast cancers are estrogen receptor (ER)-positive, making ER inhibition a longstanding therapeutic goal in this population. The current standard of care (SOC) is fulvestrant, a first-generation selective estrogen receptor degrader (SERD). Although a potent ER inhibitor, fulvestrant requires monthly intramuscular injections due to its poor oral bioavailability and suboptimal pharmacokinetics, often resulting in poor patient compliance. Moreover, secondary ESR1 mutations conferring resistance to fulvestrant emerge in approximately 40% of patients, leaving them with limited treatment options.

FWD1802 is a third-generation oral SERD designed to overcome these limitations. It exhibits high bioavailability and potent activity against both wild-type and mutant forms of ER. As a result, FWD1802 has the potential to become a new first-line SOC, replacing fulvestrant and improving outcomes for patients with ER-positive breast cancer.

Current Clinical Progress

FWD1802 monotherapy received IND approvals from the U.S. FDA and China’s NMPA in March and July 2023, respectively. The first patient was enrolled on September 12, 2023. In May 2025, FWD1802 combination therapy also received IND clearance in China and entered clinical studies. Currently, FWD1802 monotherapy is in Phase I/II trials, while the combination therapy is undergoing Phase Ib/II studies for dose escalation and expansion.

Information released to the public

1. Forward Pharma Oral SERD FWD1802 Released at SABCS 2023.

2. Latest Clinical Update of FWD1802 Phase I Study Presented at ASCO 2025.

3. FWD1802 Phase I Clinical Data Published on the Journal of Clinical Oncology.