An observational study in Multiple Myeloma and Hematologic Diseases, sponsored by Universitaire Ziekenhuizen KU Leuven. Recruiting at 17 sites in Belgium. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-25.
Sponsored by Universitaire Ziekenhuizen KU Leuven · Observational
The aim of this study is to assess the clinical efficacy of the anti-BCMA/CD3 bispecific antibody teclistamab and anti-GPRC5D/CD3 bispecific antibody talquetamab in a prospective, real-life setting in Belgium.
To assess the clinical efficacy and safety of teclistamab and talquetamab in relapsed/refractory multiple myeloma patients who have received at least 3 prior lines of treatment and who will receive teclistamab or talquetamab as the next treatment. Patients will be followed up prospectively until the end of study (24 months/2 years), or until disease progression, withdrawal of consent death or loss to follow-up, whichever occurs first. Each patient will have a monthly follow-up from baseline until 6 months of treatment. Then, data will be collected every 3 months until the end of study.
3,760 studies on the registry are indexed under Multiple Myeloma; 769 are open to participants now.
This study's planned enrollment of 100 is below the median of 150 across 486 observational studies indexed under Multiple Myeloma.
Browse Multiple Myeloma studies →Universitaire Ziekenhuizen KU Leuven is the lead sponsor of 963 studies on the registry; 267 are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
The criteria were revised on the registry on Sep 25, 2026. See what changed
100 patients with relapsed or refractory multiple myelome who will be treated with teclistamab or talquetamab
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Relapsed and refractory
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Line of therapy
A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.
“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients aged 18 years or older diagnosed with relapsed or refractory multiple myeloma, who received at least 3 prior lines of treatment. They should be refractory to at least 1 proteasome inhibitor, at least 1 immunomodulatory agent, and an anti-CD38 monoclonal antibody. After confirmation of disease progression, the patients will start treatment with teclistamab per routine clinical care or will have started with teclistamab or talquetamab treatment ≤28 days before intended screening visit
Drug: Teclistamab
Intervention is part of standard clinical care, as teclistamab and talquetamab are reimbursed for this group of patients.
Also known as: Tecvayli
Overall response rate
The primary objective is the overall response rate (partial response (PR) or better) according to the 2016 IMWG response criteria of Multiple myeloma.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Progression-free survival (PFS)
The length of time during and after the treatment during which a patient lives with the disease but it does not get worse.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Overall survival (OS)
Duration of time between start of the treatment and up to the time of death.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Incidence of (serious) adverse events
Incidence and severity of (serious) adverse events with with focus on hematological AE's (≥ grade 3), cytokine release syndrome (CRS) rate, Immune effector cell-associated neurotoxicity syndrome (ICANS) and infections (≥ grade 2) and serious adverse events related to teclistamab/talquetamab.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Depth of response
Evaluation of response in terms of depth. Assessment of response according to the 2016 IMWG response criteria of Multiple myeloma.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Time to response (TTR)
Assessment of the time it takes for a patient to achieve partial response (PR) or better.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Duration of response
Assessment of the length of time during which a patient experiences a partial response (PR) or better. It is measure from the start of treatment until disease progression or death.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Minimal Residual Disease (MRD) assessment
Evaluation of treatment efficacy by monitoring for the presence of a small number of cancer cells that are left in the body. MRD assessment will be done with Next Gen Flow (NGF) or Next Gen Sequencing (NGS).
Time frame: At suspected CR, every 6 months thereafter until end of study (maximum 24 months)
Time to next treatment (TTNT)
Assessment of the time interval between initiation of treatment with Tecvayli® and commencement of the next line of therapy.
Time frame: At baseline, monthly until end of study (maximum 24 months)
Plan to share: No
No publications or documents are linked to this record.
Started Dec 2024 (actual). Primary completion is estimated for Sep 2027, 33 months after the start.
Of 173 non-industry observational studies under Multiple Myeloma, half reached primary completion within 70 months of starting (the median), counting those still running; a quarter within 33. This study's planned 33 months is below that.
Counting every sponsor, half of 239 studies reached it within 61 months; a quarter within 30 and three quarters within 126.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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