Key takeaways
- 15–20K Estimated US PNH prevalence — median age 35, equal sex distribution
- 30–40% US PNH patients who develop venous thrombosis — leading pre-treatment cause of PNH death
- 2.4 years Mean diagnostic delay from first haemolytic symptom to confirmed PNH (International PNH Registry)
PNH's 800–1,200-patient EVH subpopulation, not the full 15,000–20,000-patient prevalence estimate, defines the commercial opportunity in the complement-inhibitor era.
PNH is a clonal haematopoietic stem cell disorder caused by somatic PIG-A mutation, leading to GPI-anchor deficiency and complement-mediated red blood cell lysis. US prevalence is estimated at 15,000–20,000 patients — median age 35, equal sex distribution. The disease spans three clinically and commercially distinct axes: haemolysis-dominant, aplasia-dominant, and thrombotic PNH, each requiring different treatment approaches and commercial micro-segmentation.
Mean diagnostic delay is 2.4 years, driven by misdiagnosis as autoimmune haemolytic anaemia, aplastic anaemia, or MDS. Approximately 15–20% of aplastic anaemia patients harbour PNH clones, forming the largest undiagnosed patient pool. Anti-C5 therapy has dramatically reduced thrombotic mortality, but 800–1,200 patients with extra-vascular haemolysis (EVH), persistent anaemia despite IV complement inhibition, define the residual unmet need and the commercial rationale for proximal complement inhibitors.
PNH disease spectrum — phenotype, burden, and treatment implication
| Phenotype | Prevalence (US est.) | Defining Feature | Key Burden | Treatment Implication |
|---|---|---|---|---|
| Haemolysis-dominant PNH | ~8,000–10,000 | LDH ≥2× ULN; FLAER clone ≥10% | Anaemia, fatigue, dysphagia, transfusion dependency | Anti-C5 first-line; EVH subpopulation switches to oral Factor B |
| Aplasia-dominant PNH | ~4,000–5,000 | AA + PNH clone; hypocellular marrow | Cytopenias; infection risk; transfusion | Immunosuppression + anti-C5 if clone ≥10%; watch for EVH after IST |
| Thrombotic PNH | ~2,000–3,000 | Unusual-site thrombosis (hepatic, cerebral) | Thrombosis leading cause of mortality; organ damage | Anti-C5 mandated; anticoagulation; thromboprophylaxis |
| EVH-dominant on C5i | ~800–1,200 | Persistent anaemia (Hgb <10–11 g/dL) on IV C5 therapy | Residual anaemia, fatigue, transfusion despite C5 control | Oral proximal complement (Factor B inhibitor) — iptacopan |
Sources: Parker C et al. Blood 2005 (International PNH Interest Group); Hillmen P et al. NEJM 2004; Schrezenmeier H et al. Ann Hematol 2014; Risitano AM et al. NEJM 2023 (EVH characterisation).
What this assessment answers
Every section answers a named commercial question your team is asking, scoped to your asset.
- What is the size and clinical characterisation of the EVH-dominant US PNH subpopulation on anti-C5 therapy, and what is the addressable patient count for iptacopan? • EVH prevalence within complement-inhibitor-treated PNH • Hgb threshold and transfusion dependency characterisation • addressable patient count for oral Factor B inhibition
- What is the diagnostic pathway for PNH in the US, and where are the largest pools of undiagnosed patients? • FLAER flow cytometry laboratory network • AA-PNH clone overlap pool • diagnostic delay by clinical presentation (haemolysis vs aplasia vs thrombosis)
- How does the PNH disease spectrum (haemolysis-dominant, aplasia-dominant, thrombotic) drive different treatment decisions and commercial micro-segmentation? • Disease spectrum sub-segmentation • treatment decision trees by phenotype • commercial micro-segmentation for targeting by PNH subtype
What's inside
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1 · A Somatic PIG-A Mutation at Median Age 35 Drives PNH's Three-Phenotype Spectrum 4 pp
- Why a single somatic PIG-A mutation causing GPI-anchor deficiency produces three clinically distinct PNH phenotypes needing different treatment approaches.
- How median age of 35 at onset and equal sex distribution shape the commercial micro-segmentation across haemolysis, aplasia, and thrombosis.
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2 · US PNH Prevalence Reaches 15,000-20,000 Patients Split Across Three Clinical Phenotypes 5 pp
- Why haemolysis-dominant disease accounts for roughly 8,000 to 10,000 of the 15,000 to 20,000 total US PNH patients.
- How aplasia-dominant and thrombotic phenotypes, at roughly 4,000-5,000 and 2,000-3,000 patients respectively, round out the three-way split.
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3 · PNH Diagnosis Takes a Mean 2.4 Years via FLAER Flow Cytometry 4 pp
- Why the 2.4-year mean diagnostic delay stems largely from misdiagnosis as autoimmune haemolytic anaemia, aplastic anaemia, or MDS.
- How FLAER flow cytometry, the confirmatory test for PNH clones, factors into closing that multi-year diagnostic gap.
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4 · 800-1,200 US Patients Have Extra-Vascular Haemolysis Despite Anti-C5 Therapy 5 pp
- Why 800 to 1,200 US patients show persistent anaemia, Hgb below 10 to 11 g/dL, despite ongoing IV anti-C5 therapy.
- How this residual anaemia burden defines the commercial rationale for proximal complement inhibitors like iptacopan.
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5 · 30-40% of PNH Patients Develop Thrombosis, the Leading Pre-Treatment Cause of Death 4 pp
- Why 30 to 40% of PNH patients develop venous thrombosis, historically the leading cause of death before anti-C5 therapy.
- How unusual-site thrombosis, hepatic and cerebral in particular, makes anti-C5 therapy mandatory for this phenotype.
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6 · 15-20% of Aplastic Anaemia Patients Carry an Undiagnosed PNH Clone 4 pp
- Why 15 to 20% of aplastic anaemia patients harbour an undiagnosed PNH clone, forming the largest undiagnosed patient pool.
- How hypocellular marrow findings in aplasia-dominant PNH, roughly 4,000 to 5,000 US patients, complicate diagnosis.
Appendix and source ledger included · 45-minute analyst readout included with delivery
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Commission this assessment
AXLRx PNH Disease Landscape is built for commercial, medical affairs, and epidemiology teams that need a rigorous, evidence-based characterisation of the US PNH patient population. Custom assessment in 72 hours.
- 1. Submit your requestSpecify indication, geography, and epidemiological focus.
- 2. Scoping callAXLRx analyst confirms subpopulation scope, data sources, and delivery format.
- 3. DeliveryResearch-verified assessment in 72 hours with optional analyst readout.
How AXLRx builds this assessment
Prepared by MoatRx analysts on the AXLRx commercial consulting engine.
PNH disease landscape is built from primary epidemiological sources, peer-reviewed clinical literature, and registry data. Epidemiological estimates are triangulated across multiple sources; all figures carry source citations.
Key sources: Parker C et al. Blood 2005 (PMID 16051736); Hillmen P et al. NEJM 2004 (PMID 14762182); Schrezenmeier H et al. Ann Hematol 2014 (PMID 24782120); Risitano AM et al. NEJM 2023 (APPLY-PNH EVH characterisation); International PNH Registry.
- Prevalence estimates verified against Parker et al. Blood 2005 and Orphanet PNH rare disease entry
- Thrombosis risk data verified against International PNH Registry primary publications
- Diagnostic delay verified against Schrezenmeier et al. Ann Hematol 2014 and International PNH Registry data
- EVH subpopulation sizing verified against APPLY-PNH trial screened and enrolled population data (NEJM 2023)
Frequently asked questions
Deliverables What formats are included with every assessment?
Every commissioned assessment includes three deliverables: a 20–30 page PDF analyst assessment with verified sources and exhibit tables, an editable Excel model (drug comparison grid, payer formulary data, or patient flow model — depending on deliverable type), and a 10–15 slide PowerPoint readout deck formatted for commercial team presentations. An optional 60-minute analyst readout call is included with all deliveries.
Sources What sources does AXLRx use, and how are findings verified?
AXLRx builds from primary sources only: the peer-reviewed natural-history and long-term outcome literature for PNH, the pivotal complement-inhibitor trial publications, and international PNH registry reporting. No secondary summaries or market research reports. Every factual claim is independently verified before inclusion. Source citations are provided for all key data points in the delivered assessment.
Customisation Can I tailor the assessment to my specific question, geography, or comparator set?
Yes. The intake form captures your indication, target geography, key comparator drugs, and the specific commercial question you need answered. A scoping call confirms scope before research starts. Custom extensions, such as additional payer markets, pipeline agent profiles, or country-specific deep-dives, can be added to any standard assessment. Commission via the intake form to start.