Progranulin

Summary

Progranulin (PGRN) is a secreted growth factor encoded by the GRN gene involved in regulation of inflammation, lysosomal function, neuronal survival, and wound healing. Haploinsufficiency of GRN is a major genetic cause of frontotemporal dementia (FTD). Recombinant progranulin and progranulin-based therapies are under active investigation for FTD, neuronal ceroid lipofuscinosis, inflammatory arthritis, and other conditions. No approved therapeutic product exists yet.

Mechanism of Action

Progranulin is a cysteine-rich secreted glycoprotein that binds to TNF receptors (TNFR1 and TNFR2) and sortilin, modulating inflammatory signaling by competing with TNF-alpha. It also activates intracellular signaling pathways including PI3K/AKT and ERK1/2, promoting cell survival, proliferation, and wound healing. Additionally, it serves as a lysosomal regulator and its deficiency is linked to neurodegeneration.

Routes of Administration

Goals & Uses

• Neuroprotection in Alzheimer's diseaseNeurologyLow
• Treatment of neuronal ceroid lipofuscinosis (NCL/Batten disease)Lysosomal Storage DisorderModerate
• Wound healing promotionTissue RepairLow
• Anti-inflammatory therapy (rheumatoid arthritis)InflammationLow
• Treatment of GRN-related frontotemporal dementiaNeurodegenerationModerate

Contraindications

• Active malignancyOncologyModerateUse caution or avoid depending on agent and context
• Known hypersensitivity to progranulin or recombinant formulation excipientsAllergy / ImmunologyHigh

Adverse Effects

• Immunogenicity / anti-drug antibody formationImmunologicalUnknown
• Potential oncogenic riskOncologyUnknown
• Infusion-related reactionsHypersensitivityUnknown

Drug Interactions

• TNF inhibitors (e.g., etanercept, adalimumab)Moderate
• ImmunosuppressantsModeratePotential interaction with immune pathways or infection risk

Population Constraints

• Pediatric patientsAgeRelative
• Patients with active or prior malignancyOncologicRelative
• Pregnant womenReproductiveRelative

Regulatory Status

• European UnionInvestigationalNo approved formulation. Research and early clinical trials ongoing for FTD and NCL indications.
• United StatesInvestigationalNo approved progranulin therapeutic. Related approaches (e.g., latozinemab/AL001 targeting sortilin to raise PGRN) have received FDA Breakthrough Therapy Designation for GRN-FTD. Gene therapy PR006 (AAV9-GRN) in Phase 1/2.
• United KingdomInvestigationalNo approved formulation. Subject to MHRA oversight for any clinical trial use.

No approved therapeutic formulation of progranulin exists in the US, EU, or UK as of 2024. Gene therapy and recombinant protein approaches targeting progranulin pathways are in early-phase clinical trials (e.g., for GRN-related FTD). Alector's AL001 (latozinemab) targets progranulin indirectly via sortilin inhibition and has received FDA Breakthrough Therapy Designation.

Evidence & Sources

No sources recorded yet.