Bulk Pharmaceutical API Sources for thioridazine

Bulk Pharmaceutical API Sources for thioridazine

Vendor	Vendor Homepage	Vendor Sku	API Url
NovoSeek		5452
ABI Chem		AC1L1KDN
ChemMol		49425847
Chembase.cn		561
Mcule		MCULE-7796139302
AN PharmaTech		AN-41562
ChemMol		99097721

Bulk Active Pharmaceutical Ingredient (API) Sources for: THIORIDAZINE

Last updated: August 6, 2025

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Introduction

Thioridazine, a phenothiazine derivative, has historically been employed as an antipsychotic agent primarily for schizophrenia treatment. Despite its declining clinical use due to notable cardiotoxicity risks, especially QT prolongation, it remains available through certain bulk API manufacturers and suppliers for preclinical research, compounding, and regulatory reasons. A comprehensive understanding of the current API sourcing landscape for thioridazine informs pharmaceutical companies, compounding pharmacies, and research institutions aiming to procure this compound reliably and safely.

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Regulatory Status and Market Overview

The global pharmaceutical landscape has largely phased out thioridazine from marketed formulations attributable to safety concerns. Nonetheless, the API persists in niche markets and academic research contexts. The FDA classifies it as a controlled substance in some jurisdictions, which influences sourcing pathways. Internationally, the compound's manufacturing and distribution are governed by strict regulations, but certain suppliers continue to produce thioridazine API under Good Manufacturing Practice (GMP) standards or for research purposes under Good Laboratory Practice (GLP).

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Key Sources of Thioridazine API

1. Established Pharmaceutical API Manufacturers

Major API producers with regulatory credibility often supply thioridazine, either as part of their portfolio of phenothiazines or as custom synthesis products for research purposes.

• MediChem (United States): Historically, MediChem has supplied high-quality APIs to research institutions. While primary focus has been on newer compounds, they historically produced phenothiazines like thioridazine (not currently confirmed for ongoing production). Their capacity to synthesize batches under GMP makes them relevant for regulated research.

• Zhejiang Hisun Pharmaceutical (China): A prominent OEM manufacturer with extensive experience in traditional antipsychotics. Their production includes phenothiazines, with capabilities for large-scale API synthesis meeting pharmaceutical specifications.

• Zhejiang Gening Pharmaceutical (China): Offers APIs including phenothiazines with potential for custom synthesis of thioridazine. Their manufacturing facilities are ISO certified, providing a baseline for quality.

• Sandoz (Novartis): Historically involved in phenothiazine production, though specific API production for thioridazine may now be limited. Their legacy API sourcing could serve as reference standards or in research.

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2. Chinese API Manufacturers and Exporters

China remains the dominant country for the production of generic APIs, including phenothiazines. Many small and medium-sized manufacturers produce thioridazine API mainly for export and research purposes.

• Shenzhen ZhiYuan Pharmaceutical: Noted for synthesizing phenothiazines at laboratory and small-scale commercial quantities, often under GMP or chemical-grade standards.

• Hainan Yuxing Pharmaceutical Co., Ltd.: Supplies phenothiazine APIs, including thioridazine, mostly targeting research markets due to regulatory restrictions.

• Shandong Xinhua Pharmaceutical: Engages in phenothiazine synthesis, with capacity to produce key compounds like thioridazine for academic and research institutions.

Note: Caution is advised given variable quality controls; verification through independent testing and certification is essential.

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3. Contract Manufacturing Organizations (CMOs)

CMOs specializing in pharmaceutical synthesis are critical intermediaries for procuring thioridazine API, especially for companies lacking in-house manufacturing capabilities.

• Eurofins Pharma CMOs: Offer custom synthesis of APIs, including phenothiazines, for research and preclinical development.

• Rochem International: Provides chemical API sourcing services, including phenothiazines, with validated quality management systems and supply chain transparency.

• Aurora Fine Chemicals: Capable of producing thioridazine API under GMP for research purposes.

Advantages: Custom synthesis, quality assurance documentation, and compliance with international standards.

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4. Academic and Grey Market Suppliers

Some universities and research institutions may synthesize and distribute thioridazine for internal research. The grey market exists where APIs are sold without regulatory oversight—necessitating rigorous due diligence before procurement.

• Research Chemical Suppliers: Companies like Sigma-Aldrich or TCI often carry thioridazine as a research chemical. While they primarily offer finished dosage forms, bulk API may be obtained through custom orders or special arrangements.

• Custom Synthesis Houses: Offer bespoke production for academic research, often sourced from Italian, Indian, or Chinese manufacturers.

Note: Be aware that APIs supplied via grey markets may lack comprehensive quality documentation and regulatory compliance, making them unsuitable for human clinical use.

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Challenges in API Sourcing

• Regulatory Restrictions: Thioridazine's classification as a controlled or restricted substance in several jurisdictions complicates legal procurement and shipment.

• Quality Variability: Differing quality standards among suppliers can impact research validity and safety.

• Limited Availability: Due to safety concerns, many manufacturers have ceased or limited API production, leading to potential shortages.

• Intellectual Property and Patent Considerations: Thioridazine's patent status mainly pertains to formulations; API synthesis occurs in the public domain, but specific production patents may exist.

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Due Diligence and Quality Assurance

Sourcing thioridazine API demands rigorous vetting:

• Certificates of Analysis (CoA): Verification of purity (>98%), residual solvent content, and heavy metals.

• Regulatory Compliance: Ensure GMP certification or equivalent where intended for preclinical or research uses.

• Vendor Qualification: Prefer suppliers with established track records, reliable supply chains, and transparent manufacturing processes.

• Independent Testing: Conduct additional in-house or third-party verification to confirm specifications.

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Emerging Trends and Future Outlook

Despite diminished clinical use, demand for thioridazine API persists in research segments. Advances in chemical synthesis, regulatory shifts, and increased scrutiny of traditional antipsychotics influence sourcing dynamics. Notably:

• Shift to Custom Synthesis: Many organizations opt for bespoke manufacturing due to limited mainstream availability.

• Regulatory Tightening: Increased controls on controlled substances may restrict or complicate API acquisition.

• Potential for Alternatives: Researchers are exploring newer antipsychotics with better safety profiles, possibly reducing reliance on traditional APIs like thioridazine.

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Key Takeaways

• Limited but Stable Supply: While not broadly available for commercial pharmaceutical production, high-quality thioridazine API remains accessible through specialized Chinese manufacturers, CMOs, and research chemical suppliers.

• Emphasis on Quality and Compliance: Choose suppliers with transparent quality documentation, GMP certification, and verifiable testing results.

• Regulatory Navigation: Be aware of legal restrictions in your jurisdiction concerning controlled substances and raw API importation.

• Due Diligence Is Critical: Prioritize thorough vetting and independent verification of any source, especially those outside official regulatory channels.

• Future Procurement Strategies: Consider custom synthesis options and establish ongoing relationships with trusted manufacturers to ensure steady API supply for research needs.

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FAQs

Q1: Is thioridazine API available for commercial pharmaceutical manufacturing today?
A: Due to safety concerns, particularly serious cardiac risks, thioridazine is largely phased out from commercial markets in many countries. API production persists mainly for research purposes and is limited to specialized suppliers.

Q2: What are the primary countries producing thioridazine API?
A: China leads in bulk API manufacturing of phenothiazines, including thioridazine, supported by various small-to-medium-sized enterprises. The United States and India historically produced APIs but now mainly focus on other compounds or rely on imports.

Q3: How can I ensure quality when sourcing thioridazine API from international suppliers?
A: Confirm the supplier's GMP certification, review Certificates of Analysis, and conduct independent testing to verify purity and compliance with pharmaceutical standards.

Q4: Are there legal restrictions on importing thioridazine API?
A: Yes. Since thioridazine is classified as a controlled substance in some jurisdictions, importation may require special licenses or permits. Always consult local regulatory authorities before procurement.

Q5: Can I obtain thioridazine API for preclinical research without regulatory hurdles?
A: Generally, yes, provided the API is acquired from reputable suppliers with appropriate documentation, and usage complies with local regulations governing research chemicals.

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References

1. FDA Drug Database. Thioridazine information.
2. World Health Organization (WHO). International drug control statutes regarding phenothiazines.
3. Chinese Pharmacopoeia. Standard listings for phenothiazines including thioridazine.
4. PharmTech.com. Phenothiazines’ manufacturing and supply trends.
5. Research Chemical Suppliers. Product catalogs and safety data sheets.

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Author Note: This analysis synthesizes publicly available information, supplier disclosures, and industry insights to guide procurement strategy. Always perform further due diligence tailored to specific regional regulations and operational needs.