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Taking people in FrancePhase 2

Tests sodium thiosulfate injections for abnormal calcium or bone growth in soft tissue

Tests injected sodium thiosulfate in people with abnormal soft tissue calcification or ossification.

Key facts

Who runs it
University Hospital, Limoges
Where
Bordeaux, Bron, Le Kremlin-Bicetre, Limoges, Paris, Paris Cedex 10, Paris Cedex 13, Rennes, Rouen Cedex, Toulouse, and Toulouse Cedex 9, FranceSee the 11 sites
Registry title
Subcutaneous Injection of Sodium Thiosulfate for Ectopic Calcifications or Ossifications. A Pilot Study
Status
Recruiting
Phase
Phase 2
People taking part
40 people, planned
Started
6 Jan 2020
Expected to end
6 Jun 2029
Type of study
Interventional
Treatments tested
  • STS
Record updated
15 September 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for people with abnormal calcium deposits (calcifications) or bone growth (ossifications) in soft tissue caused by dermatomyositis, systemic sclerosis or iPPSD2. Sodium thiosulfate is injected into the affected area.

Age
Aged 2 years or over (the record also lists a range of 6 Months to 64 Years).
Sex
All sexes can join.
Disease stage
Soft tissue ossification caused by iPPSD2, or soft tissue calcification caused by dermatomyositis or systemic sclerosis. A multidisciplinary committee must confirm that sodium thiosulfate (STS) infusion is indicated, because of the serious burden or loss of function the calcification or ossification causes.
Earlier treatment
No surgery on the calcifications or ossifications planned for the next twelve months. No anticoagulant therapy.

Main reasons for not taking part

  • Allergy to STS or to one of the other ingredients used
  • Contraindication to local injection of STS
  • Anticoagulant therapy
  • Pregnant, giving birth or breastfeeding
  • Cannot give consent, or is under legal protection or guardianship

The registry criteria, word for word

Show all 17 criteriaShow less

Who can take part

  • Patient presenting with:; ectopic ossification secondary to iPPSD2 or; ectopic calcification secondary to dermatomyositis or; ectopic calcification secondary to systemic sclerosis
  • Patient aged 2 years or over
  • Indication of STS infusion validated by a multidisciplinary committee, based on the significant morbidity and/or functional impact of the targeted calcification/ossification
  • Patient with no planned surgery of the calcifications/ossifications for the twelve coming months
  • Women of childbearing potential on highly effective contraception (such as hormonal contraception, intrauterine device, intrauterine hormone-releasing system, bilateral tubal occlusion, vasectomised partner or sexual abstinence)
  • Men with women of childbearing potential partners should use condoms during the whole treatment period and until 91 days after the last injection
  • Informed consent signed by the patient / parents
  • Patient affiliated to the social security system

Who cannot take part

  • Anticoagulant therapy
  • Allergy to STS or one of the excipients used
  • Patient undergoing psychiatric care under coercion
  • Contraindication to local injection of STS
  • Pregnant, parturient or breastfeeding woman
  • Patient deprived of freedom by a court judgment or an administrative decision
  • Legally protected adult patients (guardianship / curatorship)
  • Patient unable to give consent
  • Patient placed under judicial protection

Where in France

  • Centre hospitalier Universitaire de BordeauxBordeaux, FranceTaking people
  • Hospices Civils de LyonBron, FranceTaking people
  • Assistance Publique Hopitaux De ParisLe Kremlin-Bicetre, FranceTaking people
  • Centre Hospitalier Et Universitaire de LimogesLimoges, FranceTaking people
  • Assistance Publique Hopitaux de ParisParis, FranceTaking people
  • Assistance Publique Hopitaux De ParisParis Cedex 10, FranceTaking people
  • Assistance Publique Hopitaux De ParisParis Cedex 13, FranceTaking people
  • Centre Hospitalier Universitaire de RennesRennes, FranceTaking people
  • Centre Hospitalier Universitaire RouenRouen Cedex, FranceTaking people
  • Centre Hospitalier Universitaire de ToulouseToulouse, FranceTaking people
  • Centre Hospitalier Universitaire De ToulouseToulouse Cedex 9, FranceTaking people

About the trial

What the trial wants to find out

Ectopic soft tissue calcifications or ossifications can complicate the course of numerous diseases; most of them are rare or very rare. Even if the clinical, radiological and pathological presentation of ectopic calcifications and ossifications are different, the same hypotheses are discussed considering their hypothetical pathophysiology. Indeed, high calcium phosphate product, local cellular lesions and abnormal transdifferentiation of mesenchymal cells are regularly evoked when pathophysiology of such calcifications or ossifications are discussed. Apart from several case reports that have not been confirmed so far, no medical treatments are available, leading to significant pain and impairment of quality of life for patients. Therefore, only surgical treatment can be proposed when the volume or the consequences of these calcifications/ossifications become too important.

Read full original descriptionShow less

Sodium thiosulfate (STS) is currently used as a cyanide poisoning antagonist and a chemoprotectant against adverse effects of several chemotherapies such as Cisplatin. Numerous case reports and several studies have revealed the potential interest of STS in the treatment of uremic induced vascular or soft tissues calcifications. Recently, our group has developed an expertise in the use of STS for the treatment of ectopic soft tissue calcifications or ossifications. Considering these promising preliminary data, and their limits, we developed a strategy to treat soft tissue calcifications or ossifications based on a local administration of STS. The first results of this therapeutic strategy are highly promising and the local or systemic safety is satisfactory so far. These preliminary data also reported by others deserve to be confirmed in a prospective study.

We propose in this project to conduct a prospective open controlled phase II trial in order to assess the efficacy and the safety of intralesional administration of STS for the treatment of calcifications secondary to dermatomyositis or systemic sclerosis and ectopic ossifications secondary to pseudo-hypoparathyroidism 1a type (PHP1A/iPPSD2) (inactivating parathyroid hormone / parathyroid-hormone-related peptid (PTH/PTHrP) signalling disorder).

The group in the trial

  • TreatedTreatment being tested

    M0-M6: run-in phase (control) M6-M12: STS treatment phase

    Treatment: STS

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov and on the EU's official list of trials (CTIS).
Official title
Subcutaneous Injection of Sodium Thiosulfate for Ectopic Calcifications or Ossifications. A Pilot Study
Plain-language title
Tests sodium thiosulfate injections for abnormal calcium or bone growth in soft tissueGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 12 November 2026.
Record updated
15 September 2026