Evaluating Siplizumab for Hidradenitis Suppurativa Treatment

An Open-label Parallel Group Pilot Study to Demonstrate the Safety and Efficacy of Subcutaneous Siplizumab in the Treatment of Hidradenitis Suppurativa

EARLY_PHASE1 · University of Alabama at Birmingham · NCT06326476

This study is testing whether a new medication called siplizumab can help people with moderate to severe Hidradenitis Suppurativa who haven't found relief with other treatments.

Quick facts

PhaseEARLY_PHASE1
Study typeInterventional
Enrollment12 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of Alabama at Birmingham (other)
Drugs / interventionssiplizumab
Locations1 site (Birmingham, Alabama)
Trial IDNCT06326476 on ClinicalTrials.gov

What this trial studies

This study investigates the safety and efficacy of siplizumab, administered subcutaneously, for patients with moderate to severe Hidradenitis Suppurativa (HS). Participants will receive escalating doses of siplizumab over an 8-week period, with assessments conducted weekly and biweekly to monitor their condition and quality of life. The study aims to enroll up to 18 subjects, focusing on those who have not responded to conventional therapies. The treatment's impact on HS symptoms and patient-reported outcomes will be evaluated throughout the study.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with moderate to severe Hidradenitis Suppurativa that has not improved with conventional therapies.

Not a fit: Patients with mild HS or those who have not yet tried conventional treatments may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could provide a new therapeutic option for patients suffering from Hidradenitis Suppurativa who have not responded to existing treatments.

How similar studies have performed: While this approach is novel for Hidradenitis Suppurativa, similar studies with other treatments have shown promising results in managing chronic skin conditions.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Male or Female at least 18 years of age, and provide informed consent prior to study procedures.
* Have moderate to severe HS classified as Hurley stage II or III for at least 6 months refractory to conventional therapies with a total AN count of greater than or equal to 5 prior to enrollment/randomization
* Failed at least 1 course of oral antibiotics for treatment of HS (or demonstrated intolerance to, or had a contraindication to oral antibiotics for treatment of their HS).
* Women of Childbearing potential must have a urine pregnancy test at screening, wk 0 and prior to administration of the study medication
* Women of childbearing potential must be willing to continue a highly effective method of birth control throughout the study (oral, injected or implanted hormonal methods of contraception; placement of an intrauterine device or intrauterine system; barrier methods: condom or occlusive cap (diaphragm or cervical/vault caps) plus spermicidal foam/gel/film/cream/suppository (if available in their locale); male partner sterilization (the vasectomized partner should be the sole partner for that participant); true abstinence (when this is in line with the preferred and usual lifestyle of the participant).
* Negative screening for tuberculosis (TB) (Quantiferon Gold, T-spot) within 3 months prior to screening
* If a positive history of latent tuberculosis:

  * Currently receiving treatment for latent TB per standard of care
  * Have documentation of having completed treatment within 5 years prior to baseline
* Agree not to have a live vaccination during the study.

Exclusion Criteria:

* Any other active skin disease that in the opinion of the investigator would interfere with the assessment of HS
* Have greater than 20 draining fistulas at screening or Day 1 prior to enrollment/randomization
* Receipt of non-biologic treatments for HS within 4 weeks prior to baseline other than antibiotics or hormonal therapy
* Receipt of biologic agents within 3 months prior to baseline
* Receipt of any other investigational product within 3 months prior to baseline
* Receipt of new oral antibiotics or hormonal therapy within 6 weeks prior to baseline.

  * Subjects may be included if they are on steady dose of doxycycline or tetracycline antibiotics only for at least 6 weeks prior to baseline visit and may not change or discontinue dose during course of study.
* Receipt of intralesional kenalog injections within 2 weeks prior to baseline
* Any uncontrolled diagnosis or condition that in the opinion of the investigator will interfere with the assessments or the study.
* Currently has a malignancy or a history of a malignancy within 5 years before screen (except successfully treated non-melanoma skin cancer or cervical carcinoma in situ)
* History of an ongoing, chronic or recurrent infectious disease
* Are currently pregnant, breastfeeding, or planning to get pregnant during the study.
* Previous hypersensitivity reaction to siplizumab or to any of the components
* Known infection with HIV, hepatitis B or hepatitis C at screening or randomization.

Patients who are Hepatitis B Core antibody and/or Hep B Surface Antigen positive will be excluded from this study. Patients who are Hepatitis C ab positive will also be excluded from this study.

* Underlying condition (including, but not limited to metabolic, hematologic, renal, hepatic, pulmonary, neurologic, endocrine, cardiac, infectious or gastrointestinal) which in the opinion of the investigator significantly immunocompromises the subject and/or places the subject at unacceptable risk for receiving an immunomodulatory therapy.
* Any of the following laboratory abnormalities within 30 days of enrollment:

  * White blood count (WBC) \< 3 x 103/μL;,
  * CD4+ count below the lower limit of normal,
  * Platelet count \< 150,000 /μL,
  * Hemoglobin \< 10 g/dL,
  * ALT ≥ 2x upper limit of normal (ULN) or
  * AST ≥ 2x ULN
  * Serum creatinine \>1.5x ULN in adults.
  * Positive molecular testing of SARS-CoV-2
  * ALC less than 800 lymphocytes/mm3

Where this trial is running

Birmingham, Alabama

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Hidradenitis Suppurativa

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.