A Phase 3 interventional study of Oral ATO and IV Arsenic Trioxide in Acute Promyelocytic Leukemia (APL), Acute Promyelocytic Leukaemia and Acute Promyelocytic Leukemia With PML-RARA, sponsored by SDK Therapeutics, Inc.. Not yet recruiting. Open to participants aged 12 Years and older. Per ClinicalTrials.gov, last updated 2025-12-29.
Sponsored by SDK Therapeutics, Inc. · Phase 3, Interventional, and Treatment
LATITUDE: A Phase 3, Randomized, Open-Label, 3-Cohort, 2-Period, 2- Sequence, Crossover Trial to Evaluate the Pharmacokinetics, Safety, and Efficacy of Oral Arsenic Trioxide Versus Intravenous Arsenic Trioxide for Consolidation Therapy in Participants With Newly Diagnosed, Non-High Risk, Acute Promyelocytic Leukemia
Rationale:
SDK Therapeutics is developing an oral formulation of arsenic trioxide (ATO) for the treatment of acute promyelocytic leukemia (APL). Patients with APL are usually treated with arsenic trioxide (ATO) through an IV along with all-trans retinoic acid (ATRA) taken by mouth. Receiving ATO through an IV requires patients with APL to go to the hospital a lot and get long treatments (sometimes every day over a year of treatment). This can be hard and uncomfortable. If ATO can be taken by mouth, it would be much easier for patients and their families.
Objective:
The main objective is to show that the body absorbs the same amount of ATO whether it's taken by mouth or through an IV. Other objectives include checking if ATO taken by mouth works just as well, causes fewer heart problems, is safe, and improves quality of life compared with ATO given through an IV.
Main trial endpoints:
The main endpoint being measured is how much ATO is in the blood after 5 doses. Another important endpoint is how many patients have no signs of cancer in their blood after 3 rounds of treatment.
Secondary trial endpoints:
Other things being measured include: whether patients stay cancer-free over 2 years; changes in heart rhythm; side effects and lab test results; how patients feel during treatment; how much of ATO is in the blood; and how often patients feel bothered by side effects.
Trial design:
This is an open-label study, meaning everyone knows which treatment they are getting. Patients will get 4 rounds of treatment, each lasting 8 weeks. After that, patients will have check-ups every 3 months to assess safety and disease status for a total of 2 years.
Trial population:
The study includes adults and teens (12 years and older) who have APL, are not high-risk, and have already finished the first part of their treatment (induction) with IV ATO and ATRA.
Interventions:
There are 3 groups in the study:
Cohort A: Takes 0.15 mg/kg Oral ATO for 3 rounds, then switches to 0.15 mg/kg IV ATO for part of the 4th round.
Cohort B: Takes 0.15 mg/kg IV ATO for 3 rounds, then switches to 0.15 mg/kg Oral ATO for part of the 4th round.
Cohort C: Takes 0.15 mg/kg Oral ATO for all 4 rounds.
All cohorts also take 45 mg/m2/day ATRA during certain weeks of each round. Doctors will assess efficacy by checking bone marrow samples before and during treatment to see if the cancer is gone. Special lab tests will be used to look for cancer cells. Safety will be assessed by checking for side effects using blood tests, heart tests, physical exams, and other health checks. Quality of life will be assessed by the patients who will fill out surveys about how they feel during treatment and how much the side effects bother them. The study will also look at how often patients need to go to the doctor or hospital; how treatment affects daily life and work; and how satisfied patients are with their treatment.
134 studies on the registry are indexed under Leukemia, Promyelocytic, Acute; 16 are open to participants now.
This study's planned enrollment of 120 is above the median of 51 across 100 interventional studies indexed under Leukemia, Promyelocytic, Acute.
Browse Leukemia, Promyelocytic, Acute studies →SDK Therapeutics, Inc. is the lead sponsor of 2 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
Note: Additional inclusion/exclusion criteria may apply, per protocol.
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.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Relapsed: the illness came back after treatment had worked. Refractory: it did not respond to treatment, or stopped responding while still on it.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
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.
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
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.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
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.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
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.
Reproductive potential
Able to have children. For women this usually means from the first period until menopause, unless permanently unable to through surgery; for men, unless permanently sterile. Read who the line is about — participants, women, men, or their partners.
Criteria about it usually ask 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.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
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.
Participants will receive Oral ATO 0.15 mg/kg daily × 5 days a week from Weeks 1 to 4 in the first three 8-week cycles, IV ATO 0.15 mg/kg daily (2-hour infusion) × 5 days in Week 1 of Cycle 4, and oral ATO 0.15 mg/kg daily × 5 days a week from Weeks 2 to 4 of Cycle 4. All adult participants will receive ATRA 45 mg/m2/day in 2 divided doses as background treatment 7 days a week for 2 weeks on and 2 weeks off (Weeks 1, 2, 5 and 6 of each 8-week cycle) beginning in Cycle 1 and ending after Cycle 4 Week 2
Drug: Oral ATO · Drug: IV Arsenic Trioxide · Drug: all-trans retinoic acid (ATRA)
Participants will receive IV ATO 0.15 mg/kg daily (2-hour infusion) × 5 days a week from Weeks 1 to 4 in the first three 8-week cycles, oral ATO 0.15 mg/kg daily × 5 days in Week 1 of Cycle 4, and IV ATO 0.15 mg/kg daily (2-hour infusion) × 5 days a week from Weeks 2 to 4 of Cycle 4. All adult participants will receive ATRA 45 mg/m2/day in 2 divided doses as background treatment 7 days a week for 2 weeks on and 2 weeks off (Weeks 1, 2, 5 and 6 of each 8-week cycle) beginning in Cycle 1 and ending after Cycle 4 Week 2
Drug: Oral ATO · Drug: IV Arsenic Trioxide · Drug: all-trans retinoic acid (ATRA)
Participants will receive Oral ATO 0.15 mg/kg daily × 5 days a week from Weeks 1 to 4 of four 8-week cycles. All adult participants will receive ATRA 45 mg/m2/day in 2 divided doses as background treatment 7 days a week for 2 weeks on and 2 weeks off (Weeks 1, 2, 5 and 6 of each 8-week cycle) beginning in Cycle 1 and ending after Cycle 4 Week 2
Drug: Oral ATO · Drug: all-trans retinoic acid (ATRA)
Oral Arsenic Trioxide
Intravenous Arsenic Trioxide
all-trans retinoic acid (ATRA)
Pharmacokinetic exposure (amount of ATO in the blood)
Total 5-dose plasma AsIII AUC
Time frame: At the end of Cycle 4, Week 1 (Each cycle is 8 weeks)
Molecular Complete Response (molCR) rate
molCR rate, defined as negative/undetected for PML:RARα by RT-qPCR
Time frame: At the end of 3 Cycles of treatment (each cycle is 8 weeks)
Relapse-Free Survival (RFS)
2-year Relapse Free Survival (RFS)
Time frame: Assessed for up to 2 years after the first dose of treatment, or until disease progression/relapse or death, whichever occurs first.
Change in Fridericia-corrected QT interval (ΔQTcF interval)
Difference in QTcF between collected values
Time frame: At the end of Cycles 3 and 4 (each cycle is 8 weeks)
Adverse events
Frequency, severity, and relatedness of adverse events.
Time frame: Up to 9 months
Cardiac AEs related to elevated QTcF
Number of prolonged QTcF interval or other arrhythmias per CTCAE
Time frame: Up to 9 months
Pharmacokinetic profile
Peak Plasma Concentration (Cmax)
Time frame: At the end of Cycle 4, week 1 (Each cycle is 8 weeks)
Patient Reported Outcomes
Change from baseline as measured by the EORTC QLQ-C30
Time frame: Up to 9 months
Patient Reported Outcomes
Proportion of time "bothered by side-effects" as measured by the FACT-GP5
Time frame: Up to 9 months
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Dec 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Arsenic Trioxide
Leukemia, Promyelocytic, Acute →
SDK Therapeutics, Inc.