Last reviewed 2026-06-03 · How we verify

Natrunix

XBiotech, Inc. · Phase 2 active Small molecule ✓ Verified Jun 2026

Natrunix is a Small molecule drug developed by XBiotech, Inc.. It is currently in Phase 2 development. Also known as: True Human IgG4 monoclonal antibody, Vilamakitug.

Natrunix is being studied in clinical trials for the treatment of Rheumatoid Arthritis, Axial Spondyloarthritis, Ankylosing Spondylitis, and r-axSpA. It is being investigated in combination with methotrexate and folate in a Phase II clinical trial.

Likelihood of approval

15.3% vs 15.3% industry baseline

If approved by FDA: likely 2031–2034

Steps remaining: Phase 3 → NDA/BLA submission

Confidence: Medium

Why this estimate

Baseline phase 2 → approval rate +15.3pp
Industry-wide phase 2 drugs reach approval ~15.3% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).

Predicted approval windows by jurisdiction (conditional on FDA approval)

Regulator	Country	Likely year	Lag vs FDA
FDA	US	2031–2034	—
EMA	EU	2032–2035	+0.7 yr
MHRA	GB	2032–2035	+0.7 yr
Health Canada	CA	2032–2036	+0.9 yr
TGA	AU	2032–2036	+1.2 yr
PMDA	JP	2032–2036	+1.5 yr
NMPA	CN	2033–2037	+2.3 yr
MFDS	KR	2032–2036	+1.4 yr
CDSCO	IN	2032–2037	+1.8 yr
ANVISA	BR	2033–2037	+2.3 yr

Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).

Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.

At a glance

Generic name	Natrunix
Also known as	True Human IgG4 monoclonal antibody, Vilamakitug
Sponsor	XBiotech, Inc.
Modality	Small molecule
Therapeutic area	Other
Phase	Phase 2

Approved indications

No approved indications tracked.

Common side effects

No common side effects on file.

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Source	Used for
ClinicalTrials.gov	Trial enrolment, design, endpoints, results

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

Natrunix CI brief — competitive landscape report
Natrunix updates RSS · CI watch RSS
XBiotech, Inc. portfolio CI

Frequently asked questions about Natrunix

What is Natrunix?

Natrunix is a Small molecule drug developed by XBiotech, Inc..

Who makes Natrunix?

Natrunix is developed by XBiotech, Inc. (see full XBiotech, Inc. pipeline at /company/xbiotech-inc).

Is Natrunix also known as anything else?

Natrunix is also known as True Human IgG4 monoclonal antibody, Vilamakitug.

What development phase is Natrunix in?

Natrunix is in Phase 2.

Manufacturer: XBiotech, Inc. — full pipeline
Therapeutic area: All drugs in Other
Also known as: True Human IgG4 monoclonal antibody, Vilamakitug

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing