From India to the World: Leading Silodosin API Suppliers You Should Know
From India to the World: Leading Silodosin API Suppliers You Should Know
Last updated: September 2026. Scope: what to check when sourcing Silodosin API from an Indian manufacturer, and exactly what our own documentation covers.
Silodosin is a uroselective α1A-adrenoceptor antagonist used in BPH therapy. Its single stereocentre makes chiral control, not price, the real supplier question. We have manufactured APIs in Hyderabad since 1943 and hold ISO 9001:2015 certification covering API development and manufacture. What each certificate does and does not cover for Silodosin is set out below, so your regulatory team can read it here first.
Silodosin: a uroselective α1A-adrenoceptor antagonist
Silodosin treats the lower urinary tract symptoms of benign prostatic hyperplasia, the non-malignant prostate enlargement that shows up in men past 40. It binds α1A-adrenoceptors with high affinity, relaxes prostatic and urethral smooth muscle, and acts on afferent bladder nerves, so storage symptoms improve alongside voiding.
That selectivity is the clinical argument for the molecule and the manufacturing problem behind it. Silodosin API is a single enantiomer: C25H32F3N3O4, molecular weight 495.53 g/mol, a white to off-white crystalline powder. Carry the wrong enantiomer through the route and you do not have a yield problem. You have a rejected batch.
CAS 160970-54-7. Scoping the molecule rather than the vendor? What Silodosin API is used for in urology drug development covers the indication side.
What Indian manufacturers bring to a molecule like this
Backward integration, first. Plants that make their own intermediates control cost and lead time instead of inheriting someone else’s, which matters far more on a multi-step chiral route. Then process chemistry: stereoselective synthesis, impurity profiling and route optimisation are ordinary working skills across the Indian API sector, not specialist outsourcing.
That widens the field you choose from; it does not make every supplier in it equivalent. The price spread is real and explainable: why Silodosin API prices vary across Indian suppliers shows where the difference sits.
Qualifying more than one molecule? Start with our API portfolio.
Bio-Synth: manufacturing APIs since 1943
We are Biochemical & Synthetic Products Private Limited, and we have made APIs at Balanagar, Hyderabad, for eight decades under manufacturing licence 118/HD/AP/96/B/R. What our documentation says, stated narrowly:
| Item | What it actually covers |
|---|---|
| ISO 9001:2015 (DNV, UKAS accredited) | Certificate 156792-2014-AQ-IND-UKAS. Scope: development, manufacture and sale of active pharmaceutical ingredients, drug intermediates, biological products and liver injectable. First certified 20 August 2002. |
| WHO-GMP certificate | Drugs Control Administration, Government of Telangana, L.Dis.No. 150458/TS/2024, valid to 5 June 2027 |
| ICH Q7 | The plant is operated in line with ICH Q7 principles for API GMP. A statement of operating practice, not a third-party certification. |
| Silodosin | Manufactured and supplied against a written specification, with a certificate of analysis per batch. |
Better you see the scope stated here than your regulatory affairs team discovers it later. Why GMP certification matters for Silodosin API manufacturers explains how to read these documents properly.
Product data, the published specification and the quotation process are on our page for Silodosin API manufacturers in India.
Five questions before you qualify a supplier
Which certificates are held, and which products are named inside each one? A facility certificate is not a product approval.
What does the CoA test against: a pharmacopoeial monograph or an in-house specification?
How is batch-to-batch consistency demonstrated? Ask for the control strategy, not a reassurance.
Which ICH guidance sets the impurity and solvent limits? Q3A governs organic impurities; Q3C sets residual solvent limits by class.
What happens at scale-up? Chiral routes do not always behave the same at 10 kg and 100 kg.
Our published limits for Silodosin API: total impurities NMT 1.0%, any unspecified impurity NMT 0.1%, loss on drying NMT 1.0% w/w, residue on ignition NMT 0.1% w/w. Packing is supplied to requirements. Silodosin API powder quality standards cover what each parameter protects.
How Silodosin API is made
Where the risk sits:
| Step | Where it can go wrong |
|---|---|
| Intermediate qualification | Incoming impurity carried forward |
| Stereoselective step | Loss of enantiomeric excess |
| Chiral intermediate isolation | Incomplete resolution |
| Crystallisation and purification | Polymorph and particle size drift |
| Drying and milling | Residual solvent above ICH Q3C limits |
| QC testing and release | Nothing; this is where the earlier steps get caught |
Crystallisation and milling are what formulators feel downstream; Silodosin API particle size and purity in formulations explain why.
The portfolio around Silodosin
Useful if you would rather qualify one vendor than five.
| Therapeutic area | APIs we supply |
|---|---|
| Urology | Silodosin |
| Anti-tuberculosis | PAS Sodium, Bedaquiline |
| Cardiology | Carvedilol |
| Anti-psychotic | Amisulpride |
| Anti-diabetic | Empagliflozin, Dapagliflozin |
| Anti-histamine | Bilastine |
Each carries its own documentation set. Scope is product by product; nothing carries across automatically.
Quality and consistency, batch after batch
Release testing runs the standard sequence, appearance, identification, assay, related substances, residual solvents, loss on drying and residue on ignition, against the limits above, with a certificate of analysis for every batch.
The rest is: validated processes, controlled change management, documentation that survives an audit. ICH Q7 is explicit about all three, down to cleaning validation between campaigns.
Talking to us
Send the specification, the volume, and the market you are filing in. That is enough for a serious first conversation, and we will tell you plainly what existing documentation covers and what would have to be generated for your filing.
Contact us with your requirements.
Frequently asked questions
What is Silodosin API used for?
It goes into medicines that treat the signs and symptoms of an enlarged prostate, relaxing smooth muscle in the prostate and bladder opening to improve urine flow.
What is the molecular formula and weight of Silodosin?
C25H32F3N3O4, molecular weight 495.53 g/mol. Supplied as a white to off-white crystalline powder.
Is Silodosin soluble in water?
No. Very soluble in acetic acid, freely soluble in ethanol, insoluble in water.
How does Silodosin work?
It antagonises α1-adrenoceptors with the highest selectivity for the α1A subtype. Blocking that pathway relaxes prostatic and urethral smooth muscle and improves lower urinary tract symptoms. It also acts on afferent bladder nerves, easing storage symptoms.
Is Bio-Synth’s Silodosin covered by the WHO-GMP certificate?
No. That certificate names the two PAS Sodium products listed in the joint inspection report, and Silodosin is not among them. Our site does hold ISO 9001:2015 certification scoped to API development and manufacture, and the plant is operated in line with ICH Q7 principles.
Does Bio-Synth make Silodosin intermediates in-house?
Ask us which intermediates are made on site; the answer is part of the technical package we send with a quotation, and it is what lets lead time and cost be controlled directly.
What packing sizes are available?
Packing is supplied as per requirement. Confirm your preferred configuration with the enquiry.
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