Busulfan Patent Expiration

Busulfan is used for treating malignant conditions like leukemia and lymphoma in patients undergoing bone marrow transplants. It was first introduced by Waylis Therapeutics Llc in its drug Myleran on Approved Prior to Jan 1, 1982. Another drug containing Busulfan is Busulfex. 17 different companies have introduced drugs containing Busulfan.


Busulfan Patents

Given below is the list of patents protecting Busulfan, along with the drug name that holds that patent and the company name owning that drug.

Filter patents by

NEW
Drug Used in Drug Patent Number Drug Patent Title Drug Patent Expiry Drug Owner
Busulfex US5430057

(Pediatric)

Parenteral busulfan for treatment of malignant disease Mar 30, 2014

(Expired)

Otsuka Pharm
Busulfex US5559148

(Pediatric)

Parenteral busulfan for treatment of malignant disease Mar 30, 2014

(Expired)

Otsuka Pharm
Busulfex US5430057 Parenteral busulfan for treatment of malignant disease Sep 30, 2013

(Expired)

Otsuka Pharm
Busulfex US5559148 Parenteral busulfan for treatment of malignant disease Sep 30, 2013

(Expired)

Otsuka Pharm



Busulfan's Family Patents

Family Patents

Explore Our Curated Drug Screens

Drugs Generating Over $1 Billion in Annual Revenue
Explore the top-performing drugs that dominate the pharmaceutical industry
View List
NCE-1 Patent Expiry in the Next 1 Year
Identify opportunities as new chemical entity (NCE-1) patents approach expiry
View List
Recently Granted Patents in EP
Find the opportunity to file Oppositions
View List



Clinical Trials

Recent Clinical Trials on Busulfan:

Sometimes companies keep conducting clinical trials even after the drug's approval to discover new formulations, methods of use, or new treatment indications, so they could file for additional patents or receive regulatory exclusivity extensions, such as pediatric exclusivity, potentially delaying generic competition. Based on these recent clinical trials, generic companies need to consider the potential for new intellectual property or regulatory hurdles. These strategic moves by the drug owner might delay generic substitution or lead to additional sales of the brand drug, even after patent expiry.

Title Lead Sponsor Collaborators Status Phases
Clinical Trials
Allogeneic Hematopoietic Stem Cell Transplant for Patients With Inborn Errors of Immunity National Cancer Institute (NCI) NA RECRUITING
(Sep 22, 2026)
PHASE2
Base-Edited Hematopoietic Stem/Progenitor Cell X-Linked Severe Combined Immunodeficiency Gene Therapy National Institute of Allergy and Infectious Diseases (NIAID) NA ENROLLING BY INVITATION
(Sep 21, 2026)
PHASE1, PHASE2
Lentiviral Gene Transfer for Treatment of Children Older Than Two Years of Age With X-Linked Severe Combined Immunodeficiency (XSCID) National Institute of Allergy and Infectious Diseases (NIAID) NA RECRUITING
(Sep 18, 2026)
PHASE1, PHASE2
Pilot Trial of Allogeneic Blood or Marrow Transplantation for Primary Immunodeficiencies National Cancer Institute (NCI) NA RECRUITING
(Sep 16, 2026)
PHASE2
Base-Edited Hematopoietic Stem/Progenitor Cell Gene Therapy for Treatment of CXCR4-WHIM National Institute of Allergy and Infectious Diseases (NIAID) NA ENROLLING BY INVITATION
(Sep 15, 2026)
PHASE1, PHASE2
Donor Lymphocyte Infusion After Allogeneic Hematopoietic Cell Transplantation for High-Risk Hematologic Malignancies National Cancer Institute (NCI) NA RECRUITING
(Sep 10, 2026)
PHASE1, PHASE2
Allogeneic Hematopoietic Cell Transplantation for Peripheral T Cell Lymphoma National Cancer Institute (NCI) NA ACTIVE NOT RECRUITING
(Sep 9, 2026)
PHASE2
pCCLCHIM-p47 (Lentiviral Vector Transduced CD34 Plus Cells) in Patients With p47 Autosomal Recessive Chronic Granulomatous Disease (AR-CGD) National Institute of Allergy and Infectious Diseases (NIAID) NA ENROLLING BY INVITATION
(Sep 9, 2026)
PHASE1, PHASE2
Allogeneic Hematopoietic Stem Cell Transplant for GATA2 Mutations National Cancer Institute (NCI) NA RECRUITING
(Sep 4, 2026)
PHASE2
Therapy for Children With Advanced Stage Neuroblastoma St. Jude Children's Research Hospital NA COMPLETED
(Sep 1, 2026)
PHASE2
Allogeneic Stem Cell Transplantation for Children and Adolescents With Acute Lymphoblastic Leukaemia St. Anna Kinderkrebsforschung NA RECRUITING
(Sep 1, 2026)
PHASE2, PHASE3
Haplocompatible Transplant Using TCRα/β Depletion Followed by CD45RA-Depleted Donor Lymphocyte Infusions for Severe Combined Immunodeficiency (SCID) St. Jude Children's Research Hospital NA ACTIVE NOT RECRUITING
(Sep 1, 2026)
PHASE1, PHASE2
A First-in-Human Study of HLA-Partially to Fully Matched Allogenic Cryopreserved Deceased Donor Bone Marrow Transplantation for Patients With Hematologic Malignancies Ossium Health, Inc. NA ACTIVE NOT RECRUITING
(Sep 1, 2026)
PHASE1, PHASE2
High Dose Ruxolitinib and Allogeneic Stem Cell Transplantation in Myelofibrosis Patients With Splenomegaly M.D. Anderson Cancer Center NA RECRUITING
(Sep 1, 2026)
PHASE2
ALS20-101 Lentiviral Gene Therapy for Beta Thalassemia Children's Hospital of Philadelphia NA RECRUITING
(Sep 1, 2026)
PHASE1, PHASE2
BSB-1001 in Patients Undergoing HLA-Matched Allogenic Hematopoietic Stem Cell Transplant for AML, ALL or MDS BlueSphere Bio, Inc NA TERMINATED
(Sep 1, 2026)
PHASE1, PHASE2
Venetoclax or Placebo in Combination With Reduced-Intensity Conditioning Hematopoietic Cell (Bone Marrow/Blood Stem Cell) Transplant and as Maintenance Therapy After Transplant in Patients With Acute Myeloid Leukemia (A MyeloMATCH Treatment Trial) National Cancer Institute (NCI) NA NOT YET RECRUITING
(Sep 1, 2026)
PHASE2
Stem Cell Transplantation for Participants With Germline RUNX1 Associated Blood Cancers National Cancer Institute (NCI) NA NOT YET RECRUITING
(Aug 21, 2026)
PHASE2
Pilot Study of Reduced-Intensity Hematopoietic Stem Cell Transplant of DOCK8 Deficiency National Cancer Institute (NCI) NA ACTIVE NOT RECRUITING
(Aug 20, 2026)
PHASE2
Studies of Temozolomide in Combination With Topotecan in Refractory and Relapsed Paediatric Solid Tumours Gustave Roussy, Cancer Campus, Grand Paris NA COMPLETED
(Aug 1, 2026)
PHASE2
Reduced Intensity Conditioning (RIC) Regimen for Patients With Non-malignant Disorders Children's Hospital of Philadelphia NA COMPLETED
(Aug 1, 2026)
PHASE2
Gene Therapy After Frontline Chemotherapy in Treating Patients With AIDS-Related Non-Hodgkin Lymphoma City of Hope Medical Center NA ACTIVE NOT RECRUITING
(Aug 1, 2026)
PHASE1
The Ruxo-BEAT Trial in Patients With High-risk Polycythemia Vera or High-risk Essential Thrombocythemia RWTH Aachen University NA ACTIVE NOT RECRUITING
(Aug 1, 2026)
PHASE2
Busulfan, Fludarabine Phosphate, and Post-Transplant Cyclophosphamide in Treating Patients With Blood Cancer Undergoing Donor Stem Cell Transplant M.D. Anderson Cancer Center NA ACTIVE NOT RECRUITING
(Aug 1, 2026)
PHASE2
A Safety and Efficacy Study Evaluating CTX001 in Subjects With Severe Sickle Cell Disease Vertex Pharmaceuticals Incorporated NA COMPLETED
(Aug 1, 2026)
PHASE2, PHASE3
Allogeneic Hematopoietic Stem Cell Transplantation With Briquilimab-Based Conditioning in Participants With GATA2 Deficiency National Cancer Institute (NCI) NA ACTIVE NOT RECRUITING
(Aug 1, 2026)
PHASE2
HLA-Mismatched Unrelated Donor Peripheral Blood Stem Cell Transplantation With Reduced Dose Post Transplantation Cyclophosphamide GvHD Prophylaxis Center for International Blood and Marrow Transplant Research NA ACTIVE NOT RECRUITING
(Aug 1, 2026)
PHASE2
A Study of Bomedemstat (IMG-7289/MK-3543) Compared to Best Available Therapy (BAT) in Participants With Essential Thrombocythemia and an Inadequate Response or Intolerance of Hydroxyurea (MK-3543-006) Merck Sharp & Dohme LLC NA ACTIVE NOT RECRUITING
(Aug 1, 2026)
PHASE3
Pilot Study of Memory-like Natural Killer (ML NK) Cells After TCRαβ T Cell Depleted Haploidentical Transplant in AML Washington University School of Medicine NA RECRUITING
(Aug 1, 2026)
PHASE1, PHASE2
Ruxolitinib Before, During and After Hematopoietic Cell Transplant in Older Patients With Myelofibrosis and Myelodysplastic Syndrome/Myeloproliferative Neoplasm Overlap Syndromes Fred Hutchinson Cancer Center NA RECRUITING
(Aug 1, 2026)
PHASE2
Thiotepa-based Conditioning Regimen With De-escalated Post-graft Cyclophosphamide for Allogeneic Stem Cell Transplantation in Hematologic Malignancies Sawa Ito, MD NA RECRUITING
(Aug 1, 2026)
PHASE1
Allogeneic ORCA-Q Stem Cell Transplant for the Treatment of Relapsed and Refractory High Risk Multiple Myeloma University of California, Davis NA NOT YET RECRUITING
(Aug 1, 2026)
PHASE1
26DT052; Scaling Busulfan Dose to Body Surface Area in Children Children's Hospital of Philadelphia NA NOT YET RECRUITING
(Aug 1, 2026)
PHASE1
Base Editing for Mutation Repair in Hematopoietic Stem & Progenitor Cells for X-Linked Chronic Granulomatous Disease National Institute of Allergy and Infectious Diseases (NIAID) NA RECRUITING
(Jul 29, 2026)
PHASE1, PHASE2
Base Editing Hematopoietic Stem Cell and T Cell Gene Therapy for CD40L-HyperIgM Syndrome: Single Patient Study National Institute of Allergy and Infectious Diseases (NIAID) NA RECRUITING
(Jul 29, 2026)
PHASE1, PHASE2
A Phase II Study of Allogeneic Hematopoietic Stem Cell Transplant for Subjects With VEXAS (Vacuoles, E1 Enzyme, X-linked, Autoinflammatory, Somatic) Syndrome National Cancer Institute (NCI) NA RECRUITING
(Jul 8, 2026)
PHASE2
Stem Cell Gene Therapy for Cystinosis University of California, San Diego NA COMPLETED
(Jul 1, 2026)
PHASE1, PHASE2
Venetoclax to Improve Outcomes of Fractionated Busulfan Regimen in Patients With High-Risk AML and MDS M.D. Anderson Cancer Center NA RECRUITING
(Jul 1, 2026)
PHASE2, PHASE3
A Phase 1/3 Study of T-Cell Receptor Engineered Donor T Cells in Subjects Undergoing Allogeneic Peripheral Blood Stem Cell Transplantation TScan Therapeutics, Inc. NA RECRUITING
(Jul 1, 2026)
PHASE1
Hematopoietic Stem Cell BCL11A Enhancer Gene Editing for Sickle Cell Disease Daniel Bauer NA NOT YET RECRUITING
(Jul 1, 2026)
PHASE1
Gene Therapy for Patients With Transfusion-Dependent β-Thalassemia Prince of Wales Hospital, Shatin, Hong Kong NA NOT YET RECRUITING
(Jul 1, 2026)
PHASE2
Sorafenib, Busulfan and Fludarabine in Treating Patients With Recurrent or Refractory Acute Myeloid Leukemia Undergoing Donor Stem Cell Transplant M.D. Anderson Cancer Center NA ACTIVE NOT RECRUITING
(Jun 1, 2026)
PHASE1, PHASE2
Myeloablative Allo HSCT With Related or Unrelated Donor for Heme Disorders Masonic Cancer Center, University of Minnesota NA RECRUITING
(Jun 1, 2026)
PHASE2
A Study Evaluating Temferon in Patients With Glioblastoma & Unmethylated MGMT Genenta Science NA TERMINATED
(Jun 1, 2026)
PHASE1, PHASE2
Evaluation of Safety and Efficacy of CTX001 in Pediatric Participants With Severe Sickle Cell Disease (SCD) Vertex Pharmaceuticals Incorporated NA ACTIVE NOT RECRUITING
(Jun 1, 2026)
PHASE3
Evaluation of Safety and Efficacy of CTX001 in Pediatric Participants With Transfusion-Dependent β-Thalassemia (TDT) Vertex Pharmaceuticals Incorporated NA ACTIVE NOT RECRUITING
(Jun 1, 2026)
PHASE3
Human Leukocyte Antigen (HLA) Mismatched Unrelated Allogeneic Hematopoietic Stem Cell Transplantation He Huang NA RECRUITING
(Jun 1, 2026)
PHASE1
Allo HSCT for High Risk Hemoglobinopathies Masonic Cancer Center, University of Minnesota NA RECRUITING
(Jun 1, 2026)
PHASE2
Phase I Clinical Study of Haplo-HSCT Combined With Hypoxic 3D-Cultured Umbilical Cord MSC for the Treatment of SAA Chinese PLA General Hospital NA ENROLLING BY INVITATION
(Jun 1, 2026)
PHASE1, PHASE2
Age-Stratified Conditioning Regimen Efficacy for MDS Haplo-HSCT Peking University People's Hospital NA RECRUITING
(Jun 1, 2026)
PHASE2
Allogeneic Hematopoietic Stem Cell Transplantation for Chronic Granulomatous Disease (CGD) With an Alemtuzumab, Busulfan and TBI-based Conditioning Regimen Combined With Cytokine (IL-6, +/- IFN-gamma) Antagonists National Institute of Allergy and Infectious Diseases (NIAID) NA RECRUITING
(May 12, 2026)
PHASE1, PHASE2
High Dose Peripheral Blood Stem Cell Transplantation With Post Transplant Cyclophosphamide for Patients With Chronic Granulomatous Disease National Institute of Allergy and Infectious Diseases (NIAID) NA ACTIVE NOT RECRUITING
(May 8, 2026)
PHASE1, PHASE2
Busulfan, Etoposide, and Total-Body Irradiation in Treating Patients Undergoing Donor Stem Cell or Bone Marrow Transplant for Advanced Hematologic Cancer City of Hope Medical Center NA COMPLETED
(May 1, 2026)
PHASE2
Donor Peripheral Stem Cell Transplant in Treating Patients With Advanced Hematologic Cancer or Other Disorders City of Hope Medical Center NA ACTIVE NOT RECRUITING
(May 1, 2026)
PHASE2
Reduced-intensity, Related-donor Bone Marrow Transplantation Followed by High-dose Cyclophosphamide for Hematologic Cancers Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins NA TERMINATED
(May 1, 2026)
PHASE2
Personalized NK Cell Therapy in CBT M.D. Anderson Cancer Center NA RECRUITING
(May 1, 2026)
PHASE2
Haploidentical Transplantation With Pre-Transplant Immunosuppressive Therapy for Patients With Sickle Cell Disease City of Hope Medical Center NA RECRUITING
(May 1, 2026)
PHASE1
Naive T Cell Depletion for Preventing Chronic Graft-versus-Host Disease in Children and Young Adults With Blood Cancers Undergoing Donor Stem Cell Transplant Fred Hutchinson Cancer Center NA ACTIVE NOT RECRUITING
(May 1, 2026)
PHASE2
A Modified Dose of Rabbit Anti-thymocyte Globulin (rATG) in Children and Adults Receiving Treatment to Help Prepare Their Bodies for a Bone Marrow Transplant Memorial Sloan Kettering Cancer Center NA ACTIVE NOT RECRUITING
(May 1, 2026)
PHASE2
A Gene Transfer Study Inducing Fetal Hemoglobin in Sickle Cell Disease (GRASP, BMT CTN 2001) David Williams NA ACTIVE NOT RECRUITING
(May 1, 2026)
PHASE2
Emapalumab With Post-Transplant Cyclophosphamide, Tacrolimus and Mycophenolate Mofetil for the Prevention of Graft-versus-Host Disease After Donor Reduced-Intensity Hematopoietic Cell Transplant City of Hope Medical Center NA RECRUITING
(May 1, 2026)
PHASE1
FLUDARABINE-TREOSULFAN REDUCED INTENSITY CONDITIONING REGIMEN PRIOR HAPLOIDENTICAL STEM CELL TRANSPLANTATION WITH POST TRANSPLANTATION CYCLOPHOSPHAMIDE FOR OLDER AND/OR FRAIL PATIENTS WITH AML Institut Paoli-Calmettes NA NOT YET RECRUITING
(May 1, 2026)
PHASE2
ß-Thalassemia Major With Autologous CD34+ Hematopoietic Progenitor Cells Transduced With TNS9.3.55 a Lentiviral Vector Encoding the Normal Human ß-Globin Gene San Rocco Therapeutics NA ACTIVE NOT RECRUITING
(Apr 1, 2026)
PHASE1
Venetoclax and Sequential Busulfan, Cladribine, and Fludarabine Phosphate Before Donor Stem Cell Transplant in Treating Patients With Acute Myelogenous Leukemia or Myelodysplastic Syndrome M.D. Anderson Cancer Center NA ACTIVE NOT RECRUITING
(Apr 1, 2026)
PHASE2
High-Dose Post-Transplant Cyclophosphamide and Bortezomib (CyBor) for the Prevention of Graft-versus-Host Disease Following Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) NYU Langone Health NA COMPLETED
(Apr 1, 2026)
PHASE2
Peritransplant Ruxolitinib for Patients With Primary and Secondary Myelofibrosis Fred Hutchinson Cancer Center NA ACTIVE NOT RECRUITING
(Apr 1, 2026)
PHASE2
Safety And Efficacy Of TKI Cessation For CML Patients With Stable Molecular Response In A Real World Population Baylor College of Medicine NA ACTIVE NOT RECRUITING
(Apr 1, 2026)
PHASE2
Transplantation of Clustered Regularly Interspaced Short Palindromic Repeats Modified Hematopoietic Progenitor Stem Cells (CRISPR_SCD001) in Patients With Severe Sickle Cell Disease Mark Walters, MD NA RECRUITING
(Apr 1, 2026)
PHASE1, PHASE2
Itacitinib for the Prevention of Graft Versus Host Disease M.D. Anderson Cancer Center NA ACTIVE NOT RECRUITING
(Apr 1, 2026)
PHASE2
Ruxolitinib and Chidamide Intensified Bu/CY Conditioning Regimen Chinese PLA General Hospital NA RECRUITING
(Apr 1, 2026)
PHASE2
Phase III Study Comparing GVHD Prophylaxis With ATG-thymoglobulin to ATLG-grafalon in Elderly Patients With Acute Myeloid Leukemia or Myelodysplasic Syndrome and Receiving an Allogeneic Hematopoietic Stem Cell Transplantation With a 10/10 HLA Matched Unrelated Donor Assistance Publique - Hôpitaux de Paris NA RECRUITING
(Apr 1, 2026)
PHASE3
Gene Editing For Sickle Cell Disease St. Jude Children's Research Hospital NA RECRUITING
(Apr 1, 2026)
PHASE1
Proton-Based Total Marrow Irradiation for Allogeneic Transplantation in High-Risk AML/MDS Institute of Hematology and Blood Transfusion, Czech Republic NA RECRUITING
(Apr 1, 2026)
PHASE1, PHASE2
Gene Transfer for Severe Combined Immunodeficiency, X-linked (SCID-X1) Using a Self-inactivating (SIN) Gammaretroviral Vector David Williams NA COMPLETED
(Mar 1, 2026)
PHASE1, PHASE2
Fludarabine and Busulfan vs. Fludarabine, Busulfan and Total Body Irradiation Hackensack Meridian Health NA TERMINATED
(Mar 1, 2026)
PHASE3
Graft Versus Host Disease-Reduction Strategies for Donor Blood Stem Cell Transplant Patients With Acute Leukemia or Myelodysplastic Syndrome (MDS) Fred Hutchinson Cancer Center NA RECRUITING
(Mar 1, 2026)
PHASE2
Cord Blood Transplant in Children and Young Adults With Blood Cancers and Non-malignant Disorders Memorial Sloan Kettering Cancer Center NA RECRUITING
(Mar 1, 2026)
PHASE2
Evaluation of Efficacy and Safety of a Single Dose of CTX001 in Participants With Transfusion-Dependent β-Thalassemia and Severe Sickle Cell Disease Vertex Pharmaceuticals Incorporated NA RECRUITING
(Mar 1, 2026)
PHASE3
MT2021-08T Cell Receptor Alpha/Beta Depletion PBSC Transplantation for Heme Malignancies Masonic Cancer Center, University of Minnesota NA RECRUITING
(Mar 1, 2026)
PHASE2
Study on the Efficacy and Safety of the TmBU Conditioning Regimen in High-risk or Relapsed/Refractory Acute Leukemia The First Affiliated Hospital of Soochow University NA RECRUITING
(Mar 1, 2026)
PHASE2
A Platform Protocol to Investigate Post-Transplant Cyclophosphamide-Based Graft-Versus-Host Disease Prophylaxis in Patients With Hematologic Malignancies Undergoing Mismatched Unrelated Donor Peripheral Blood Stem Cell Transplantation Center for International Blood and Marrow Transplant Research NA RECRUITING
(Mar 1, 2026)
PHASE2


Busulfan Generic API Manufacturers

Several generic applications have been filed for Busulfan. The first generic version for Busulfan was by American Regent Inc and was approved on Dec 22, 2015. And the latest generic version is by Prinston Pharmaceutical Inc and was approved on Sep 11, 2024.

Given below is the list of companies who have filed for Busulfan generic, along with the locations of their manufacturing plants worldwide.