A Phase 1 interventional study of Pelabresib and Phenytoin in Healthy Participants, sponsored by Novartis Pharmaceuticals. Recruiting at 1 site in United Kingdom. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-09-22.
Sponsored by Novartis Pharmaceuticals (part of Novartis) · Phase 1, Interventional, and Other
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The purpose of this study is to assess the effect of multiple doses of phenytoin, a strong cytochrome P450 (CYP)3A4 inducer, and itraconazole, a strong CYP3A4 inhibitor, on the pharmacokinetic (PK) profile of DAK539 (hereafter referred to as pelabresib) after a single dose in healthy participants. In addition, the safety and tolerability of a single dose of pelabresib with and without the co-administration of itraconazole or phenytoin will be evaluated.
This is a 2-part, open-label, drug-drug interaction (DDI) study to assess the effect of phenytoin (a strong CYP3A4 inducer) and itraconazole (a strong CYP3A4 inhibitor) on the pharmacokinetics of pelabresib in healthy participants.
The study includes two parts, each with two treatment periods. In Part 1, participants will be administered pelabresib in Treatment Period 1 and pelabresib and phenytoin in Treatment Period 2.
In Part 2, participants will be administered pelabresib in Treatment Period 1 and pelabresib and itraconazole in Treatment Period 2.
Novartis Pharmaceuticals is the lead sponsor of 2,718 studies on the registry; 221 are open to participants now.
Of its 585 completed or terminated interventional studies of FDA-regulated products, 438 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
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.
Vital signs after being supine for 5 minutes in a quiet environment must be within the following ranges:
Exclusion Criteria:
Other protocol-defined inclusion/exclusion criteria may apply.
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.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
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.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Single dose of pelabresib (Treatment Period 1), followed by a single dose of pelabresib plus repeated doses of phenytoin (Treatment Period 2)
Drug: Pelabresib · Drug: Phenytoin
Single dose of pelabresib (Treatment Period 1), followed by a single dose of pelabresib plus repeated doses of itraconazole (Treatment Period 2)
Drug: Pelabresib · Drug: Itraconazole
Oral dosing
Also known as: DAK539
Oral dosing
Oral dosing
Part 1 and 2: Maximum observed plasma concentration (Cmax) of pelabresib
Pharmacokinetic (PK) parameters determined using the actual recorded sampling times and non- compartmental method(s) from the pelabresib plasma concentration-time data.
Time frame: From pre-dose up to 48 or 72 hours after pelabresib administration
Part 1 and 2: Area under the plasma concentration-time curve from time 0 to the last measurable concentration sampling time (AUClast) of pelabresib
PK parameters determined using the actual recorded sampling times and non- compartmental method(s) from the pelabresib plasma concentration-time data.
Time frame: From pre-dose up to 48 or 72 hours after pelabresib administration
Part 1 and 2: Area under the plasma concentration-time curve from time 0 to infinity (AUCinf) of pelabresib
PK parameters determined using the actual recorded sampling times and non- compartmental method(s) from the pelabresib plasma concentration-time data.
Time frame: From pre-dose up to 48 or 72 hours after pelabresib administration
Part 1 and 2: Time to reach maximum plasma concentration (Tmax) of pelabresib
PK parameters determined using the actual recorded sampling times and non- compartmental method(s) from the pelabresib plasma concentration-time data.
Time frame: From pre-dose up to 48 or 72 hours after pelabresib administration
Part 1 and 2: Apparent plasma clearance (CL/F) of pelabresib
Pharmacokinetic (PK) parameters determined using the actual recorded sampling times and non- compartmental method(s) from the pelabresib plasma concentration-time data.
Time frame: From pre-dose up to 48 or 72 hours after pelabresib administration
Part 1 and 2: Apparent volume of distribution during the terminal elimination phase (Vz/F) of pelabresib
Pharmacokinetic (PK) parameters determined using the actual recorded sampling times and non- compartmental method(s) from the pelabresib plasma concentration-time data.
Time frame: From pre-dose up to 48 or 72 hours after pelabresib administration
Part 1 and 2: Terminal elimination half-life (T1/2) of pelabresib
Pharmacokinetic (PK) parameters determined using the actual recorded sampling times and non- compartmental method(s) from the pelabresib plasma concentration-time data.
Time frame: From pre-dose up to 48 or 72 hours after pelabresib administration
Part 1 and 2: Incidence of adverse events (AEs) and serious adverse events (SAEs)
Number of participants with AEs and SAEs, including changes in vital signs, electrocardiograms and laboratory values qualifying and reported as AEs.
Time frame: Up to approximately 30 days after the last dose of study drug (Day 48 in Part 1 and Day 40 in Part 2)
Plan to share: No — Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent review panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations. This trial data availability is according to the criteria and process described on https://www.clinicalstudydatarequest.com/.
No publications or documents are linked to this record.
Started Sep 2026 (actual). Primary completion is estimated for Nov 2026, 2 months after the start.
How these figures are worked out, and which studies are left out of them.
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Studies of the drugs tested here: CPI-0610 · Phenytoin · Itraconazole