Fenfluramine

Evidence Level: L5

Predicted Indications: 4

Fenfluramine

Pharmacist Assessment Report

Fenfluramine: From Obesity to Proximal 16p11.2 Microdeletion Syndrome

One-Sentence Summary

Fenfluramine was originally used to treat obesity, including monogenic obesity, and is now marketed in Australia as an oral solution (Fintepla). The TxGNN model predicts it may be effective for proximal 16p11.2 microdeletion syndrome, but there are currently 0 clinical trials and 0 publications supporting this prediction, so it rests on the model score alone.

Quick Overview

Item	Content
Original Indication	Obesity disorder; monogenic obesity (from the knowledge graph, as no approved indication text is recorded for the ARTG entry)
Predicted New Indication	Proximal 16p11.2 microdeletion syndrome
TxGNN Prediction Score	0.9993
Evidence Level	L5
Australia Market Status	Listed on the PBS Schedule (1 of 1 items) – TGA (ARTG) registration status is not included in this data
Number of PBS Items	1 (valid: 1)
Recommended Decision	Hold

Why is This Prediction Reasonable?

Detailed mechanism of action data is not available in the data compiled for this report. Based on general pharmacological knowledge, fenfluramine is a serotonin-releasing agent that also modulates 5-HT2 and sigma-1 receptors. It was first used as an appetite suppressant and is now approved in many markets for seizures in Dravet syndrome and Lennox-Gastaut syndrome.

The 16p11.2 deletion is associated with obesity, epilepsy and neurodevelopmental features. This gives a plausible, though indirect, link to both the original obesity indication and fenfluramine’s antiseizure activity through serotonergic pathways.

No trial or published study in the compiled data tests this link. The very high score (0.9993) comes from the TxGNN model (deep learning) and may reflect similarities the model learned between related diseases, not biological evidence. It should not be read as clinical evidence.

Clinical Trial Evidence

Currently no related clinical trials registered.

Literature Evidence

Currently no related literature available for this predicted indication.

Australia Market Information

ARTG Number	Product Name	Dosage Form	Approved Indication
ARTG 14833Q	Fintepla	Oral solution 2.2 mg (as hydrochloride) per mL, 360 mL	Not recorded in the compiled data

Safety Considerations

Knowledge-graph contraindication signals (these come from drug-disease links in the TxGNN knowledge graph, not from approved label text): hypertension and hypertensive disorder, pulmonary hypertension, glaucoma, type 1 and type 2 diabetes mellitus, diabetic ketoacidosis, and substance abuse/dependence.
Drug Interactions: The interaction query returned 100 records. Those listed in the compiled data include these Major interactions:
- Fentanyl
- Dextromethorphan
- Tramadol
- Alfentanil
- Almotriptan
Several Moderate interactions were also listed, including:
- Abciximab
- Abiraterone
- Acalabrutinib
- Acarbose
- Codeine
- Dihydrocodeine
- Ibuprofen
- Ketorolac
- Salbutamol
- Formoterol
- Ethanol
- Pioglitazone
- Alogliptin
- Albiglutide
- Trastuzumab emtansine

Warnings and contraindications from the label were not available. Please refer to the TGA-approved Product Information (PI) for full safety information. Fenfluramine’s historical withdrawal as an anti-obesity agent because of valvular heart disease and pulmonary hypertension is well documented, and it is relevant to any new use.

Conclusion and Next Steps

Decision: Hold

Rationale: The prediction has no supporting clinical trials or literature (Evidence Level L5). The mechanistic link is plausible but unproven, and the known cardiac and pulmonary safety concerns call for caution.

To proceed, the following is needed:

Mechanism of action data and a direct mechanistic analysis for 16p11.2 microdeletion syndrome
A literature and trial search specific to fenfluramine in 16p11.2 deletion, including ANZCTR and international registries
The TGA Product Information (warnings, contraindications and approved indications) for Fintepla
A cardiac and pulmonary safety monitoring plan, such as echocardiography
Review of the interactions with serotonergic and opioid drugs
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.