Thrombocytopenia Trajectories in Antiphospholipid Syndrome: A Multicenter Cohort Study

NCT07757789 — Not applicable, Recruiting, 200 participants, New Valley University

ClinicalTrials Daily · Areas · Conditions · Drugs · Sponsors ·

Thrombocytopenia Trajectories as a Dynamic Biomarker of Clinical Severity and Survival in Antiphospholipid Syndrome: A Multicenter Cohort Study

Registry	NCT07757789
Status	Recruiting
Phase	Not applicable
Study type	Interventional; na, single group, masking: none, diagnostic
Enrollment	200 (Estimated)
Sponsor	New Valley University (Other)
Conditions	Antiphospholipid Syndrome
Interventions	Platelet count (Diagnostic test)
Dates	start 2026-07-01, primary completion 2027-09-25 (estimated), completion 2027-12-31 (estimated), first posted 2026-08-11, last updated 2026-08-11
Locations	1 site in Egypt

-Summary

Thrombocytopenia is common in antiphospholipid syndrome (APS) and is now included in the 2023 ACR/EULAR APS criteria as an important non criteria/hematologic feature. Persistent or low-moderate thrombocytopenia independently predicts reduced long-term survival in APS, with hazard ratios for mortality around 2.7-4.4, and is associated with a severe disease phenotype and thrombotic deaths.

Expand all sections · Collapse all

+Detailed description

Thrombocytopenia also independently predicts recurrent thrombosis, pregnancy morbidity, and severe extra criteria events in primary APS, correlates with higher damage indices and thrombotic/neurological involvement, and is enriched in high-risk thrombotic APS clusters with poorer prognosis. Existing studies treat thrombocytopenia as a static exposure (present/absent, baseline level). The prognostic value of longitudinal platelet trajectories (persistent vs intermittent vs transient vs absent thrombocytopenia) for global clinical severity and survival has not been systematically evaluated.

+Arms and interventions

Arm	Type	Interventions	Description
Antiphospholipid syndrome patients	Experimental	Diagnostic Test: Platelet count	* Definite APS by Sydney criteria (thrombotic and/or obstetric) with persistent aPL positivity. * ≥3 documented platelet counts over ≥12 months before inclusion (to allow trajectory modeling)

Platelet count (Diagnostic test): Longitudinal platelet counts (routine visits, hospitalizations) will be extracted. • Using group based trajectory modeling or latent class mixed models, patients will be assigned to data driven platelet trajectory classes, anticipated as: 1. Stable normal (no thrombocytopenia) 2. Transient thrombocytopenia (recovery to normal) 3. Intermittent/fluctuating thrombocytopenia 4. Persistent mild-moderate thrombocytopenia (e.g., 50-149×10⁹/L) 5. Persistent severe thrombocytopenia (<50×10⁹/L)

+Outcome measures

Primary outcomes

All-cause mortality [From date of diagnosis until the date of death from any cause,assessed up to 5 years"]

Secondary outcomes

number recurrent thrombotic event [Through study completion, an average of 5 years.]

+Eligibility

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Age ≥18 years.
* Definite APS by Sydney criteria (thrombotic and/or obstetric) with persistent aPL positivity.
* ≥3 documented platelet counts over ≥12 months before inclusion (to allow trajectory modeling)

Exclusion Criteria:

* Thrombocytopenia clearly attributable to non APS causes (e.g., chemotherapy, myelodysplastic syndromes, cirrhosis, HIV).
* Concomitant conditions strongly affecting survival independent of APS (e.g., metastatic cancer), at investigator discretion

+Locations (1)

Facility	City	Country	Status
New Valley University	Al Khārjah, Kharga Oasis	Egypt	Recruiting

+Publications

Chen C, Zhang A, Cheng J, Yao Z, Meng J, Qin Y, Lu Q, Li Y, Liu X, Li T, Hou C, Tang Y, Liu H, Xu N, Dong S, Li X, Xu F, Guo J, Li C. Identification of Three Distinct Subgroups in Antiphospholipid Syndrome: Implication for Sex Differences and Prognostic Outcomes from a Multicenter Study. Adv Sci (Weinh). 2025 Apr;12(15):e2415291. doi: 10.1002/advs.202415291. Epub 2025 Feb 18. PMID 39965097
Gamal S, Mohamed S, Moghazy A. Thrombocytopenia in a cohort of primary and secondary antiphospholipid syndrome patients: Relation to clinical, laboratory manifestations and damage index. Arch Rheumatol. 2022 Jan 23;37(2):252-260. doi: 10.46497/ArchRheumatol.2022.9088. eCollection 2022 Jun. PMID 36017208
Jin J, Xu X, Hou L, Hou Y, Li J, Liang M, Li C. Thrombocytopenia in the first trimester predicts adverse pregnancy outcomes in obstetric antiphospholipid syndrome. Front Immunol. 2022 Aug 18;13:971005. doi: 10.3389/fimmu.2022.971005. eCollection 2022. PMID 36059524
Jin J, Zhang M, Cai X, Hou Y, Xiang X, Hou L, Li J, Li C. Severe thrombocytopenia is associated with adverse pregnancy outcomes in patients with obstetric antiphospholipid syndrome. Eur J Med Res. 2025 Jun 9;30(1):465. doi: 10.1186/s40001-025-02675-4. PMID 40490817