CLINICAL TRIALS PROFILE FOR BUSULFAN

505(b)(2) Clinical Trials for busulfan

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
New Combination	NCT01643668 ↗	Busulfan/Clofarabine + Allogeneic Stem Cell Transplantation	Completed	Massachusetts General Hospital	Phase 2	2012-07-01	This research is a phase II clinical trial. Phase II clinical trials test the effectiveness of an investigational intervention to learn whether it works in treating a specific cancer. "Investigational" means that the study intervention is still being studied and that research doctors are trying to find out more about it. It also means that the FDA has not yet approved this study intervention for your type of cancer. All participants on this study are treated in an identical manner. The investigators are doing this study because there continues to be a significant risk of relapse of disease after reduced intensity transplantation. In studies which have compared transplants using high-doses of chemotherapy and/or radiation versus reduced intensity transplants, patients undergoing reduced intensity transplants appear to have higher rates of relapse, but lower rates of toxicity and complication. This study attempts to utilize clofarabine, a newer chemotherapy agent shown to be quite active in AML, ALL, and MDS, to increase the anti-tumor effects of the conditioning regimen without accumulating unacceptable toxicity. The reduced intensity allogeneic stem cell transplantation procedure involves giving you chemotherapy in relatively less intense doses to suppress your immune system. This is followed by an infusion of healthy blood stem cells from a matched related donor or a matched unrelated volunteer donor. It is hoped that these donor cells can eventually then attack any cancer cells which remain. In this research study, the investigators are looking to see how well this new combination of busulfan and clofarabine works in reduced intensity allogeneic stem cell transplantation. By "works" the investigators mean to analyze safety, ability of donor cells to engraft (take hold), as well as measures of complications including toxicity, infections, graft-vs-host disease (GVHD), and relapse.

All Clinical Trials for busulfan

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00001561 ↗	Active Immunization of Sibling Bone Marrow Transplant Donors Against Purified Myeloma Protein of the Recipient Undergoing Allogeneic Bone Marrow Transplantation	Completed	National Cancer Institute (NCI)	Phase 3	1996-11-01	Both patients and marrow donors are treated on Regimen A; patients then proceed to Regimen B. The following acronyms are used: ABM Allogeneic Bone Marrow BU Busulfan, NSC-750 CF Leucovorin calcium, NSC-3590 CTX Cyclophosphamide, NSC-26271 G-CSF Granulocyte Colony-Stimulating Factor (source not specified) GM-CSF Granulocyte-Macrophage Colony-Stimulating Factor (Hoechst/Immunex), NSC-613795 GVHD Graft-vs.-Host Disease Mesna Mercaptoethane sulfonate, NSC-113891 MTX Methotrexate, NSC-740 PP Unconjugated Myeloma Immunoglobulin plasma paraprotein, NSC-684150 PP-KLH Myeloma immunoglobulin plasma paraprotein vaccine, NSC-678327, with keyhole limpet hemocyanin TBI Total-Body Irradiation TSPA Thiotepa, NSC-6396 Regimen A (Donor and Patient): Vaccine Therapy with Immunoadjuvant. PP-KLH (individual myeloma immunoglobulin plasma paraprotein vaccine prepared from recipient's plasma paraprotein and conjugated with KLH); and PP; with GM-CSF. Regimen B (Patient): Myeloablative Radiotherapy and 2-Drug Combination Chemotherapy or 2-Drug Combination Myeloablative Chemotherapy followed by Hematopoietic Rescue with Growth Factor Support and GVHD Prophylaxis followed by Vaccine Therapy with Immunoadjuvant. TBI; and CTX/TSPA; or BU/CTX; followed by ABM; with G-CSF; and CYSP; MTX/CF; followed by PP-KLH; with GM-CSF.
NCT00002502 ↗	Combination Chemotherapy and Bone Marrow Transplantation in Treating Patients With Leukemia or Myelodysplastic Syndrome	Completed	National Cancer Institute (NCI)	Phase 2	1992-07-01	RATIONALE: Drugs used in chemotherapy use different ways to stop cancer cells from dividing so they stop growing or die. Combining chemotherapy with bone marrow transplantation may allow the doctor to give higher doses of chemotherapy drugs and kill more cancer cells. PURPOSE: Phase II trial to study the effectiveness of combination chemotherapy consisting of busulfan and cyclophosphamide followed by bone marrow transplantation in treating patients who have acute or chronic leukemia or myelodysplastic syndrome.
NCT00002502 ↗	Combination Chemotherapy and Bone Marrow Transplantation in Treating Patients With Leukemia or Myelodysplastic Syndrome	Completed	Memorial Sloan Kettering Cancer Center	Phase 2	1992-07-01	RATIONALE: Drugs used in chemotherapy use different ways to stop cancer cells from dividing so they stop growing or die. Combining chemotherapy with bone marrow transplantation may allow the doctor to give higher doses of chemotherapy drugs and kill more cancer cells. PURPOSE: Phase II trial to study the effectiveness of combination chemotherapy consisting of busulfan and cyclophosphamide followed by bone marrow transplantation in treating patients who have acute or chronic leukemia or myelodysplastic syndrome.
NCT00002547 ↗	Chemotherapy and Bone Marrow Transplantation in Treating Patients Acute Myeloid With Leukemia or Myelodysplastic Syndrome	Completed	National Cancer Institute (NCI)	Phase 2	1987-08-01	RATIONALE: Drugs used in chemotherapy use different ways to stop cancer cells from dividing so they stop growing or die. Combining chemotherapy with bone marrow transplantation may allow the doctor to give higher doses of chemotherapy and kill more cancer cells. PURPOSE: Phase II trial to study the effectiveness of bone marrow transplantation following combination chemotherapy in treating patients with acute myeloid leukemia or myelodysplastic syndrome .

Clinical Trial Conditions for busulfan

Condition Name

Condition Name for busulfan
Intervention	Trials
Leukemia	142
Myelodysplastic Syndromes	89
Lymphoma	87
Acute Myeloid Leukemia	61

Condition MeSH

Condition MeSH for busulfan
Intervention	Trials
Leukemia	264
Myelodysplastic Syndromes	181
Preleukemia	166
Leukemia, Myeloid, Acute	157

Clinical Trial Locations for busulfan

Trials by Country

Trials by Country for busulfan
Location	Trials
Canada	80
China	76
France	44
Italy	42
Germany	33

Trials by US State

Trials by US State for busulfan
Location	Trials
Texas	91
New York	79
California	67
Maryland	67
Washington	56

Clinical Trial Progress for busulfan

Clinical Trial Phase

Clinical Trial Phase for busulfan
Clinical Trial Phase	Trials
PHASE3	2
PHASE2	20
PHASE1	8

Clinical Trial Status

Clinical Trial Status for busulfan
Clinical Trial Phase	Trials
Completed	252
Recruiting	135
Unknown status	67

Clinical Trial Sponsors for busulfan

Sponsor Name

Sponsor Name for busulfan
Sponsor	Trials
National Cancer Institute (NCI)	166
M.D. Anderson Cancer Center	56
Fred Hutchinson Cancer Research Center	35

Sponsor Type

Sponsor Type for busulfan
Sponsor	Trials
Other	853
NIH	207
Industry	95

Busulfan: Clinical-Trial Update, Market Assessment, and Forward Projections

Last updated: April 27, 2026

What is busulfan’s clinical development status?

Busulfan is an established cytotoxic alkylating agent used primarily as a conditioning therapy in hematopoietic stem cell transplantation (HSCT). Most “busulfan trials” activity is concentrated in (1) formulation and dosing comparisons, (2) transplant conditioning regimens (busulfan plus fludarabine or cyclophosphamide), and (3) therapeutic drug monitoring (TDM) strategies to improve exposure control.

Clinical activity pattern (what is typically being updated)

• TDM approaches: studies evaluate how best to target exposure (AUC or steady-state concentrations) and how to adjust dosing.
• Conditioning regimen comparisons: trials compare transplant outcomes across conditioning combinations that include busulfan.
• Formulation and administration: comparisons cover oral versus IV delivery, dosing schemes, and pharmacokinetic (PK) behavior.

Where the clinical body of work is concentrated

• HSCT conditioning in malignant and non-malignant hematologic indications.
• Adult and pediatric cohorts with emphasis on PK-guided dosing and toxicity management.

Regulatory and label-linked constraints that shape trials

• Busulfan use in HSCT is practice-driven and protocol-driven; trial designs often aim to reduce hepatic veno-occlusive disease (VOD) and other exposure-related toxicities through PK/TDM.
• Evidence generation commonly focuses on exposure-response and regimen tolerability rather than new mechanism-of-action claims.

Which busulfan products define today’s competitive landscape?

Busulfan’s market is shaped by the availability of IV busulfan (used widely in transplant conditioning because of dosing consistency and reduced variability versus oral) and by branded or authorized generics where supply and reimbursement matter.

Key product archetypes in the market

• IV busulfan for conditioning regimens prior to HSCT.
• Oral busulfan (still used in some centers and in specific protocols, but often displaced by IV where PK and exposure consistency are prioritized).

Competitive drivers

• Supply continuity for IV busulfan.
• Contracting and reimbursement in transplant centers.
• Clinical standard-of-care adoption of PK/TDM-based dosing practices.
• Center protocols that specify IV vs oral use, dose adjustment rules, and monitoring cadence.

How big is the busulfan HSCT conditioning market?

Busulfan demand is a function of: 1) number of HSCT procedures (autologous and allogeneic) that use busulfan-containing conditioning,
2) proportion of patients receiving busulfan within those regimens,
3) dosing intensity and repeat conditioning events (relapse/second transplant), 4) share shifting between oral and IV formulations.

Because busulfan is a component drug and not the only determinant of conditioning choice, market sizing typically uses transplant procedure volumes and regimen adoption rates.

Market sizing framework (projection logic)

A robust projection for busulfan should be modeled as:

• Target addressable population: HSCT candidates requiring busulfan-containing conditioning.
• Penetration: percent of conditioning regimens that include busulfan.
• Dosing utilization: mg per patient and regimen-specific dosing (including PK/TDM changes).
• Unit economics: blended price per regimen in hospital purchasing.

Practical implication for investors and R&D planners

• Growth is tied more closely to HSCT volume trends and regimen protocol shifts than to major new clinical efficacy breakthroughs.
• The most material forecast upside usually comes from increased HSCT uptake and continued migration toward IV busulfan.

What do current market drivers imply for near-term growth?

Demand-side drivers

• HSCT volume growth: broader transplant eligibility and improved supportive care expand the addressable pool over time.
• Protocol standardization: busulfan remains a standard conditioning backbone in many protocols, which supports durability of demand.
• Exposure management adoption: centers implementing TDM seek busulfan formulations that enable consistent dosing and predictable PK.

Supply and access drivers

• IV busulfan supply constraints can swing quarterly demand.
• Contracting outcomes affect whether centers use busulfan at formulation level (IV vs oral) and at unit pricing.

Cost and reimbursement drivers

• Hospital acquisition cost and reimbursement alignment drive formulary inclusion.
• Conditioning packages are reimbursed through a mixture of diagnosis-related group systems and payer coverage structures by geography.

What constraints affect busulfan’s market growth?

• Toxicity and exposure variability are operational barriers. Centers increasingly require PK/TDM processes, which increase workflow burden and can slow adoption in low-resource settings.
• Generic substitution and pricing pressure: once supply increases and generics scale, ASP compression can offset volume growth.
• Protocol evolution: conditioning regimens can shift toward alternatives if outcome profiles or toxicity burdens change in specific patient subsets.

Clinical trial update: what is the actionable read-through?

For business planning, the “signal” in busulfan’s clinical updates is usually operational:

• whether a center’s protocol tightens TDM targets,
• whether dosing schedules shift,
• and whether IV use continues to replace oral.

In practice, this tends to preserve busulfan’s “conditioning core” status even when clinical programs are not novel.

Investment-relevant conclusion

• Near-term R&D value is more likely tied to formulation improvements, PK/TDM optimization, and manufacturing continuity rather than new mechanism differentiation.

What is the forward projection for busulfan through the next 5 to 10 years?

A forward projection should be anchored on HSCT procedure growth and IV formulation share, with pricing pressure as the counterweight.

Base-case projection (qualitative)

• Volume: modest-to-steady growth driven by HSCT expansion and ongoing busulfan protocol inclusion.
• Value: slower growth or flat-to-moderate growth due to price erosion from generic competition and tender dynamics.

Upside case

• Faster adoption of busulfan-containing conditioning and stronger migration to IV.
• Improved supply continuity and tender wins that maintain market share.
• Expanded HSCT utilization in borderline-eligibility populations where conditioning protocols use busulfan.

Downside case

• More protocol substitution away from busulfan in key subgroups.
• Sustained ASP compression with higher generic penetration.
• Supply disruptions that reduce center access.

Where do clinical and market metrics intersect for decision-making?

Operational KPIs to track

• HSCT transplant volumes by geography and center type.
• Proportion of busulfan-containing conditioning regimens (IV share vs oral share).
• TDM protocol adoption rates and how they influence dose adjustments (and, indirectly, mg utilization per patient).
• Formulary inclusion and tender outcomes for IV busulfan.

R&D/portfolio KPIs

• Formulation stability and PK predictability performance.
• Manufacturing yield and supply reliability for IV busulfan.
• Clinical protocol alignment for TDM-based dosing.

Key takeaways

• Busulfan’s clinical development activity is predominantly HSCT conditioning-focused, with updates centered on PK/TDM dosing and regimen integration rather than new mechanism claims.
• Market demand is driven by HSCT procedure volumes and by the share of busulfan-containing regimens, with IV busulfan typically capturing the operational preference for consistent exposure.
• Forward growth is likely modest on volume with pricing pressure shaping value. Upside depends on HSCT uptake and continued IV share expansion; downside depends on protocol substitution and sustained ASP erosion.
• Actionable planning should prioritize supply continuity, formulary/tender execution, and operational protocol fit for TDM workflows.

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FAQs

1) Is busulfan still used as a core HSCT conditioning agent?
Yes. Busulfan remains a standard conditioning component in many HSCT protocols, with clinical practice emphasizing exposure management through PK/TDM.

2) What matters most for busulfan market share: clinical outcomes or supply access?
Both. In practice, share is often decided by availability of IV supply, contract pricing, and center protocol fit for PK/TDM workflows.

3) Do new busulfan trials typically change practice?
They tend to refine dosing exposure targets and regimen operations more than they replace busulfan with alternative conditioning agents.

4) How does IV versus oral busulfan affect adoption?
IV busulfan generally supports more consistent dosing/exposure, which accelerates use in centers that formalize PK/TDM and standardized conditioning schedules.

5) What is the dominant driver of busulfan revenue growth over the next decade?
HSCT volume growth and IV share expansion, tempered by generic price compression.

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References

[1] U.S. Food and Drug Administration. Drug Trials Snapshots: Busulfan. FDA. https://www.accessdata.fda.gov/scripts/cder/daf/ (accessed 2026-04-27).
[2] European Medicines Agency. Busulfan (Assessment reports and EPAR resources). EMA. https://www.ema.europa.eu/ (accessed 2026-04-27).
[3] National Cancer Institute. Busulfan (Drug Information). NCI. https://www.cancer.gov/ (accessed 2026-04-27).
[4] StatPearls. Busulfan. (Clinical summary and HSCT conditioning context). https://www.ncbi.nlm.nih.gov/books/ (accessed 2026-04-27).