Conestat Alfa
| Evidence Level: L1 | Predicted Indications: 10 |
Table of Contents
Conestat Alfa: From Hereditary Angioedema (Approved Use) to C1 Inhibitor Deficiency
One-Sentence Summary
Conestat alfa (Ruconest) is a recombinant human C1 esterase inhibitor, already marketed in the US for hereditary angioedema (HAE). The TxGNN model’s top prediction is C1 inhibitor deficiency, the disease that underlies HAE types I/II, so this is effectively the approved use rather than true repurposing. It is supported by 41 clinical trials and 20 publications, but much of the trial evidence is class-level (other C1-INH products).
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Hereditary angioedema (acute attacks). The US license record has no indication text, so this comes from the pack’s mechanistic rationale. |
| Predicted New Indication | C1 inhibitor deficiency |
| TxGNN Prediction Score | 99.999% (model rank 101) |
| Evidence Level | L1 |
| US Market Status | ✓ Marketed |
| Number of NDAs | 1 (BLA125495) |
| Recommended Decision | Proceed with Guardrails |
Why is This Prediction Reasonable?
Detailed mechanism-of-action data is not recorded in the pack. Conestat alfa is a recombinant human C1 esterase inhibitor (a serpin) produced in transgenic rabbits. It replaces the missing or dysfunctional C1-INH and restores control of the classical complement, contact/kallikrein-kinin and fibrinolytic cascades. This limits bradykinin generation, which drives the swelling attacks.
C1 inhibitor deficiency is the root cause of HAE types I/II, so the prediction is direct protein replacement in the deficient state. It is not a distant mechanistic leap. Its short half-life limits use for routine prophylaxis. Its established role is treating acute attacks.
The same knowledge-graph link also appears as the rank 3 prediction, “hereditary angioedema with C1Inh deficiency”, with the same evidence base and the same decision.
The other predictions (ranks 2 and 4-10) are weak. They include serpinopathy, Glanzmann thrombasthenia, Scott syndrome, pseudo-von Willebrand disease, and several platelet or thrombocytopenia disorders. They have no trials or literature and no plausible C1-INH mechanism, and they are likely graph-proximity artifacts. All are Hold (L5).
Clinical Trial Evidence
The 10 most relevant of 41 registered trials are listed. Trials of plasma-derived C1-INH are class-level evidence, not conestat alfa itself. Product identity for trials not named in the pack was inferred from titles and should be verified.
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT06690047 | Phase 4 | Completed | 5 | Ruconest for the HAE prodrome, to prevent progression to acute attacks. Directly on-drug but very small. |
| NCT00261053 | Phase 2 | Completed | 14 | Open-label recombinant human C1-INH for acute HAE attacks, exploring efficacy, safety and PK/PD. |
| NCT00262301 | Phase 3 | Completed | 75 | Randomized, placebo-controlled, double-blind trial of recombinant C1-INH for acute HAE attacks. |
| NCT01188564 | Phase 3 | Completed | 75 | Placebo-controlled trial with open-label extension of rhC1INH 50 U/kg, confirming efficacy, safety and immunogenicity. |
| NCT00225147 | Phase 2/3 | Completed | 77 | Randomized, placebo-controlled study of recombinant C1-INH in acute HAE attacks. |
| NCT02247739 | Phase 2 | Completed | 32 | Placebo-controlled 3-period crossover of recombinant C1-INH for attack prophylaxis. |
| NCT01359969 | Phase 2 | Completed | 57 | Open-label Ruconest 50 U/kg in children aged 2-13 with acute HAE attacks. |
| NCT03697187 | N/A (registry) | Completed | 152 | Real-world safety registry of Ruconest in HAE. |
| NCT06679426 | Phase 3 | Not yet recruiting | 24 | Conestat alfa vs placebo for ACE-inhibitor-induced angioedema, a possible expansion beyond HAE. |
| NCT00289211 | Phase 3 | Completed | 83 | Placebo-controlled trial of plasma-derived C1-INH in acute HAE attacks (class-level). |
Literature Evidence
The 10 most relevant of 20 publications are listed. The Lancet 2017 paper is a Phase 2 RCT, so it is typed RCT on the basis of its title. The 2018 paper is typed RCT in the source classification, but its title and abstract read as an expert review.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 28754491 | 2017 | RCT (Phase 2, crossover) | Lancet | Recombinant human C1-INH evaluated for prophylaxis of HAE attacks. |
| 30021471 | 2018 | RCT (per source classification) | Expert Rev Clin Immunol | Conestat alfa for prophylaxis in adults and adolescents with HAE. |
| 22946752 | 2012 | Review | BioDrugs | Efficacy shown in two similar randomized, double-blind, placebo-controlled trials in HAE attacks. |
| 23420425 | 2013 | Systematic review | Pneumonol Alergol Pol | Compares conestat alfa, human C1-INH and icatibant for acute HAE attacks. |
| 24801469 | 2014 | Cohort | Allergy Asthma Proc | Home treatment of 65 edematous episodes in two patients, assessing real-life efficacy and safety. |
| 31982824 | 2020 | Cohort | Int Immunopharmacol | Home use of rhC1-INH for attacks and short-term prophylaxis, evaluating efficacy and safety. |
| 22171564 | 2012 | Cohort | BioDrugs | Effects of recombinant C1-INH on coagulation and fibrinolysis, addressing thromboembolic concern. |
| 27940765 | 2016 | Guideline | Pediatrics | Management of children with HAE due to C1-INH deficiency. |
| 26250409 | 2015 | Review | Immunotherapy | Recombinant replacement therapy for HAE due to C1-INH deficiency. |
| 39675680 | 2025 | Study | J Allergy Clin Immunol | Clinical response and blood transcriptome pathways before and after treatment of HAE prodromes vs active attacks. |
US Market Information
| Authorization Number | Product Name | Dosage Form | Manufacturer |
|---|---|---|---|
| BLA125495 | Ruconest | Injection, powder, for solution (injectable) | Pharming Healthcare Inc. |
The license record contains no approved-indication text.
Safety Considerations
- Drug Interactions: The DDI query returned no records.
- Points flagged in the evidence review:
- Hypersensitivity, because the product is derived from rabbit milk.
- Thromboembolic risk, which is a known concern with C1-INH products.
- Labeled patient-selection limits.
No formal warnings or contraindications were captured in the pack. Please refer to the package insert for full safety information.
Conclusion and Next Steps
Decision: Proceed with Guardrails
Rationale: C1-INH replacement in C1-INH deficiency is mechanistically direct. There are several completed Phase 3 and Phase 2 trials of recombinant C1-INH, plus registry and real-world data. The drug is already marketed in the US. The evidence is strong, but much of the trial base is class-level, and the pack has no label text or safety data.
To proceed, the following is needed:
- The Ruconest package insert (indications, warnings, contraindications), to confirm the approved indication and complete the safety screen.
- Verification of product identity for trials graded on class-level evidence (for example NCT02247739).
- A monitoring plan for hypersensitivity and thromboembolic events.
- A separate evaluation of ACE-inhibitor-induced angioedema (NCT06679426) if that expansion is pursued.
This report is for research reference only and does not constitute medical advice. Predicted indications require clinical validation before any application.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.