Druggability & Clinical Context
Druggability
Low
Score: 0.44
Druggability Analysis
Structural Tractability0.70
Key Metrics
PDB Structures:
2
Known Drugs:
2
Approved:
0
In Clinical Trials:
2
Drug Pipeline (2 compounds)
1 Phase II · 1 Phase I
Therapeutic Areas:Neurodegenerative diseases (Alzheimer's disease, Parkinson's disease) Neuroinflammation Chronic obstructive pulmonary disease (COPD) Atherosclerosis Multiple sclerosis Amyotrophic lateral sclerosis (ALS)
Druggability Rationale: CX3CR1 demonstrates moderate druggability (0.60) as a GPCR with established structural validation (2.8 Å resolution, 2 PDB structures) and two clinical-stage antagonists (AZD8797 in Phase 2, JNJ-39758979 in Phase 1). However, the GPCR class presents typical challenges including G-protein coupling selectivity and potential off-target cardiovascular effects that have historically complicated GPCR drug development.
Mechanism: GPCR antagonist modulating microglial activation and neuroinflammation
Drug Pipeline (2 compounds)
1 Phase II · 1 Phase I
Known Drugs:AZD8797 (phase_2) — COPD
JNJ-39758979 (phase_1) — atherosclerosis
Structural Data:PDB (2) ✓AlphaFold ✓Cryo-EM ✓
Binding Pocket Analysis:CX3CR1 possesses a canonical GPCR orthosteric binding pocket formed by transmembrane helices 3, 5, 6, and 7, with structural data (PDB: 7XBW, 7XBX) likely revealing ligand-binding modes and allosteric modulation sites. The fractalkine binding interface and potential allosteric pockets offer opportunities for both orthosteric and allosteric antagonist design to optimize selectivity and CNS penetration.
Selectivity & Safety Considerations
CX3CR1 selectivity against other chemokine receptors (particularly CX3CR1 homologs and closely-related GPCRs like CCR5, CXCR4) represents a key challenge. The microglial-restricted expression pattern provides some inherent selectivity advantage, though systemic GPCR off-target binding remains a concern for peripherally-active antagonists.
Clinical Trials (7)
Relevant trials from ClinicalTrials.gov
By Phase
PHASE1: 3 · PHASE2: 4
PHASE2
NCT00946569
n=116
Asthma
Interventions: JNJ39758979, Placebo
Sponsor: Johnson & Johnson Pharmaceutical Research & Development, L.L | Started: 2009-08
PHASE1
NCT01442545
n=21
Rheumatoid Arthritis
Interventions: JNJ-39758979 / MTX
Sponsor: Johnson & Johnson Pharmaceutical Research & Development, L.L | Started: 2011-08
PHASE1
NCT01081821
n=61
Healthy
Interventions: single dose NJ-39758979/ matching placeb, multi-dose JNJ-39758979 /matching placeb
Sponsor: Johnson & Johnson Pharmaceutical Research & Development, L.L | Started: 2010-02
PHASE1
NCT01068223
n=24
Histamine Induced Itch
Interventions: A:JNJ-39758979/Placebo #1, C:Cetirizine/JNJ-39758979 Matching Place, B: JNJ-39758979 Matching Placebo /Placeb
Sponsor: Johnson & Johnson Pharmaceutical Research & Development, L.L | Started: 2010-02
PHASE2
NCT01497119
n=88
Dermatitis, Atopic
Interventions: JNJ-39758979, 300 mg, JNJ-39758979, 100 mg, Placebo
Sponsor: Janssen Pharmaceutical K.K. | Started: 2011-10
PHASE2
NCT01480388
Active Rheumatoid Arthritis; Rheumatoid
Interventions: Placebo/JNJ-39758979 (300 mg/d), JNJ-39758979 (10 mg), JNJ-39758979 (30 mg)
Sponsor: Janssen Research & Development, LLC | Started: 2011-12
PHASE2
NCT01493882
Asthma
Interventions: Placebo, JNJ-39758979 30 mg/d, JNJ-39758979 100 mg/d
Sponsor: Johnson & Johnson Pharmaceutical Research & Development, L.L | Started: 2012-03