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CSL300

CSL Behring · Phase 2 active Small molecule

CSL300 is a Complement inhibitor Small molecule drug developed by CSL Behring. It is currently in Phase 2 development for Paroxysmal nocturnal hemoglobinuria (PNH). Also known as: Clazakizumab.

CSL300 is a recombinant human monoclonal antibody that targets the complement system.

CSL300 is a recombinant human monoclonal antibody that targets the complement system. Used for Paroxysmal nocturnal hemoglobinuria (PNH).

Likelihood of approval
16.3% 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).
  • Immunology slight uplift +1.0pp
    Mature endpoint landscape (ACR, DAS28, PASI) makes immunology approvals slightly more predictable.
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 nameCSL300
Also known asClazakizumab
SponsorCSL Behring
Drug classComplement inhibitor
TargetC5
ModalitySmall molecule
Therapeutic areaImmunology
PhasePhase 2

Mechanism of action

CSL300 works by inhibiting the complement system, specifically the C5 component, to prevent excessive inflammation and tissue damage. This mechanism is thought to be beneficial in treating conditions associated with complement system dysregulation.

Approved indications

Common side effects

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.

SourceUsed for
ClinicalTrials.govTrial 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:

Frequently asked questions about CSL300

What is CSL300?

CSL300 is a Complement inhibitor drug developed by CSL Behring, indicated for Paroxysmal nocturnal hemoglobinuria (PNH).

How does CSL300 work?

CSL300 is a recombinant human monoclonal antibody that targets the complement system.

What is CSL300 used for?

CSL300 is indicated for Paroxysmal nocturnal hemoglobinuria (PNH).

Who makes CSL300?

CSL300 is developed by CSL Behring (see full CSL Behring pipeline at /company/csl-behring).

Is CSL300 also known as anything else?

CSL300 is also known as Clazakizumab.

What drug class is CSL300 in?

CSL300 belongs to the Complement inhibitor class. See all Complement inhibitor drugs at /class/complement-inhibitor.

What development phase is CSL300 in?

CSL300 is in Phase 2.

What are the side effects of CSL300?

Common side effects of CSL300 include Headache, Nausea, Infusion-related reactions.

What does CSL300 target?

CSL300 targets C5 and is a Complement inhibitor.

Related

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