Drug Overview

The GS-pan-Notch inhibitor AL102 (also known as AL102 or BMS-906024) is an investigational, orally bioavailable small molecule designed to treat cancers driven by the Notch signaling pathway. It belongs to a class of drugs known as gamma-secretase inhibitors (GSIs).

AL102 is specifically engineered to block the activity of all four Notch receptors (Notch 1, 2, 3, and 4). This “pan-Notch” approach is particularly critical for treating Desmoid Tumors (aggressive fibromatosis), where the Notch pathway is a key driver of tumor growth.

Generic Name: AL102.
Drug Class: Gamma-Secretase Inhibitor (GSI) / Pan-Notch Inhibitor.
Target: Gamma-secretase enzyme (and the resulting Notch signaling pathway).
Route of Administration: Oral (Tablet).
FDA Approval Status: Investigational. As of March 2026, AL102 is not yet FDA-approved. However, it has received Orphan Drug Designation and Fast Track Designation from the FDA for the treatment of progressing desmoid tumors. It is currently in a pivotal Phase II/III clinical trial known as the RINGSIDE study.

What Is It and How Does It Work? (Mechanism of Action)

AL102 functions by “cutting the power line” of the Notch signaling pathway, which is essential for cell differentiation, proliferation, and survival in certain tumors.

The Role of Gamma-Secretase

Notch receptors are proteins that sit on the surface of cells. When a signal (ligand) binds to these receptors, the gamma-secretase enzyme acts as a “molecular scissor.” It cleaves the Notch receptor, releasing the Notch Intracellular Domain (NICD). This NICD then travels to the cell nucleus, where it “turns on” genes that cause the tumor to grow and resist therapy.

Molecular Level Mechanisms

Selective Inhibition: AL102 binds to the gamma-secretase enzyme complex with high affinity.
Cleavage Blockade: By inhibiting gamma-secretase, AL102 prevents the “second cut” of the Notch receptor. This means the NICD can never be released.
Gene Silencing: Without the NICD in the nucleus, the oncogenic (cancer-causing) Notch target genes remain “off.”
Tumor Regression: In desmoid tumors, blocking Notch signaling leads to a decrease in the production of collagen and other fibers that make up the tumor, resulting in tumor shrinkage and pain relief.
Anti-Angiogenesis: AL102 also inhibits Notch 4 signaling, which can disrupt the tumor’s ability to form new blood vessels (angiogenesis).

FDA-Approved Clinical Indications

There are currently no FDA-approved indications for AL102.

It is strictly available through participation in clinical trials. Its primary research focus includes:

Progressing Desmoid Tumors: For adult and pediatric patients whose tumors are growing or causing significant symptoms and cannot be removed surgically.
Adenoid Cystic Carcinoma (ACC): Investigated in patients with Notch-activating mutations.
T-cell Acute Lymphoblastic Leukemia (T-ALL): Early-phase research focused on Notch 1-driven leukemia.

Dosage and Administration Protocols

Because AL102 is an investigational drug, the dosage is determined by clinical trial protocols. The following reflects the regimen utilized in the pivotal RINGSIDE trial.

Treatment Detail	Research Specification
Route	Oral (Tablet)
Primary Dose	1.2 mg once daily (continuously).
Schedule	Taken every day without planned breaks (unless toxicity occurs).
Pediatric Dosing	Often calculated based on body surface area ($mg/m^2$).
Monitoring	Frequent imaging (MRI) is required every 3–6 months to assess tumor volume changes.

Clinical Efficacy and Research Results

As of 2024 through early 2026, data from the RINGSIDE Study (NCT04871282) has shown significant clinical promise.

Tumor Volume Reduction: In Phase II data, approximately 50% or more of patients experienced a partial response (significant tumor shrinkage).
MRI Changes: Unlike traditional chemotherapy, AL102 causes desmoid tumors to change “color” (T2 signal intensity) on MRIs, indicating that the tumor tissue is being replaced by inactive scar tissue before it actually shrinks.
Pain Management: Many patients reported a decrease in the “Global Impression of Change” (GIC) and significant reductions in tumor-related pain and stiffness within the first few cycles of treatment.
Stability: Early results suggest that the “duration of response” (how long the tumor stays small) is durable, with many patients remaining stable for over 18 months.

Safety Profile and Side Effects

The side effects of AL102 are largely “class effects” associated with gamma-secretase inhibitors, primarily affecting the skin and gastrointestinal tract.

Common Side Effects (>25%):

Diarrhea: The most frequent side effect, usually manageable with over-the-counter anti-diarrheal medication.
Skin Rash: Including dry skin or acne-like eruptions.
Fatigue: A general sense of tiredness.
Stomatitis: Mouth sores or inflammation of the gums.
Changes in Taste (Dysgeusia).

Serious or Monitoring Concerns:

Ovarian Toxicity: GSIs can interfere with normal ovarian function. In pre-menopausal women, AL102 can cause temporary or permanent amenorrhea (loss of menstrual period) and infertility.
Hypophosphatemia: Low levels of phosphorus in the blood, which may require supplementation.
Elevated Liver Enzymes: Mild to moderate spikes in ALT or AST, requiring regular blood monitoring.

Research Areas

In the fields of Stem Cell and Regenerative Medicine, AL102 is a vital tool for studying “Niche-Tumor Interaction.” Because desmoid tumors are “fibroblastic” in nature, researchers are using AL102 to understand how Notch inhibitors can “re-program” the tumor environment. There is ongoing research investigating whether Notch inhibitors like AL102 can prevent the “scarring” (fibrosis) that occurs after bone marrow transplants or in cases of Graft-versus-Host Disease (GvHD).

Patient Management and Practical Recommendations

Pre-treatment Tests:

Pregnancy Test: Mandatory for women of childbearing potential, as AL102 is highly toxic to a developing fetus.
Baseline MRI: To serve as a “map” for measuring future tumor shrinkage.
Liver and Kidney Panel: To ensure baseline organ health.

Precautions:

Contraception: Highly effective non-hormonal contraception must be used during treatment and for several months after the last dose.
Ovarian Preservation: Pre-menopausal women should consult a fertility specialist regarding egg freezing before starting Notch inhibitors.

“Do’s and Don’ts” List:

DO take the tablet at the same time every day to maintain a steady level of the drug in your blood.
DO stay well-hydrated, especially if you experience mild diarrhea.
DON’T take any new supplements or herbal medications (especially St. John’s Wort) without oncology approval, as they can interfere with how the liver breaks down AL102.
DON’T ignore changes in your skin; early use of medical-grade moisturizers can prevent severe rashes.

Legal Disclaimer

The information provided is for educational purposes only and does not constitute medical advice. GS-pan-Notch inhibitor AL102 is an investigational agent and is not approved by the US FDA for any indication. It is available only through participation in approved clinical trials. Always consult with a qualified oncologist or hematologist regarding your diagnosis and eligibility for research.