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Fulvestrant in combination with abemaciclib

Sermonix Pharmaceuticals Inc. · Phase 3 active Small molecule

Fulvestrant blocks estrogen receptors while abemaciclib inhibits CDK4/6, together suppressing hormone-driven breast cancer cell growth through dual pathway inhibition.

Fulvestrant blocks estrogen receptors while abemaciclib inhibits CDK4/6, together suppressing hormone-driven breast cancer cell growth through dual pathway inhibition. Used for Hormone receptor-positive, HER2-negative advanced or metastatic breast cancer.

At a glance

Generic nameFulvestrant in combination with abemaciclib
SponsorSermonix Pharmaceuticals Inc.
Drug classSelective estrogen receptor degrader (SERD) + CDK4/6 inhibitor combination
TargetEstrogen receptor (ER) and CDK4/CDK6
ModalitySmall molecule
Therapeutic areaOncology
PhasePhase 3

Mechanism of action

Fulvestrant is a selective estrogen receptor degrader (SERD) that binds to and degrades estrogen receptors, eliminating estrogen-dependent signaling in breast cancer cells. Abemaciclib is a CDK4/6 inhibitor that blocks cell cycle progression by preventing the transition from G1 to S phase. Together, this combination targets both the estrogen receptor pathway and cell cycle checkpoints, providing complementary mechanisms to overcome resistance and improve efficacy in hormone receptor-positive breast cancer.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results