Subsequent New Drug - SND Regulations & Clinical Trials

A subsequent New Drug (SND) refers to an approved Drug that is modified and requires fresh regulatory approval before marketing. The process includes defined application cases, detailed evaluation, and sometimes clinical trial support. Regulatory authorities check safety, quality, and effectiveness at each step. Clinical trial guidelines ensure ethical conduct and reliable data generation, helping to confirm that the modified Drug is safe and suitable for patient use under CDSCO SND guidelines.

What is a Subsequent New Drug and SND Application?

A subsequent New Drug or SND, refers to a medicine that has already received approval from the Central Licensing Authority (CLA) but is now intended to be re-introduced with certain changes. These changes may include a different therapeutic use (indication), altered dosage, a new dosage form, or a different route of administration which is important as per subsequent New Drug India regulations.1

The SND application is the regulatory process through which approval is sought for such modifications. It mainly applies to Drugs that were approved within the last four years or Drugs that are already approved but are now being proposed with updated or additional claims. This process ensures that any change made to an approved drug is properly evaluated before it is marketed for the new claims.2

When is a Subsequent New Drug Application Required?

SND application regulations are put in place to ensure that any changes are thoroughly evaluated by the regulatory authorities before approval as part of the SND approval process.

The application is required in the following cases:

Approved bulk Drug (within 4 years) is reconsidered.
Approved formulation (within 4 years) is modified or reused.
Approved Drug is proposed for a new indication.
Approved Drug is introduced in a new dosage form or route of administration.
Approved Drug is developed as a modified or controlled release dosage form.
Approved Drug is proposed with additional or different strength.

These cases indicate that approval is required whenever significant changes are made to an already approved drug.2

Subsequent New Drug Regulatory Pathway

The regulator process for a Subsequent New Drug (SND) in India is carried out under the framework of the Central Drugs Standard Control Organization (CDSCO), in accordance with the Drugs and Cosmetics Rules, 1945. It involves a structured approval process for drugs already approved but now proposed with modified or new claims following CDSCO SND guidelines. The Subsequent New Drug regulatory pathway includes the following steps:

Application Submission and Fees (Form 44): Applicant submits application Form-44 along with fees for grant of permission to manufacture or import subsequent New Drug for approved Drug with new changes. Fees for subsequent Dew Drug application for import/ manufacturing within one year of its initial approval (Form 44) is Rs 50000/- and after one year it is Rs 15000/-. Application is verified for completeness and No Deficiency Letter is issued.
Technical Evaluation and SEC Review: The Subject Expert Committee (SEC) Review on clinical aspects & approval of CT/BE protocols and reports is carried out. Recommendations to Firms and Recommendation Compliance (If any) are ensured. Review of BE report is done where required for subsequent New Drug approval.3,5
CMC Review, Inspection and Testing: Review of chemistry, manufacturing and controls (CMC) Data is conducted to ensure satisfactory CMC data. Inspection (If required) is performed. IPC NOC to applicant and IPC test report with compliance to specification is required.3,5
Final Approval and Marketing Authorization: Final approval is issued in Form 45 – for import & marketing of Drug product. Form 46 is granted- for manufacturing & marketing of Drug product. Form 45A and Form 46A may also be issued for drug substance. The approval is based on compliance with NDCT and regulatory requirements.

The regulatory pathway for a SND involves key steps in approval such as application submission, evaluation, and final authorization to ensure the safety, quality, and effectiveness of modified or existing Drugs before they are marketed.

Subsequent New Drugs Clinical Trial
Figure 1

Subsequent New Drugs Clinical Trial Requirements

Subsequent New Drugs Clinical trial requirements are governed under NDCT and relevant rules of the Drugs & Cosmetics Rules, 1945 under subsequent new drug India framework. The clinical trial requirements include the following:2,6

Permission from Licensing Authority: No clinical trial for a new drug shall be conducted except under, and in accordance with the permission, in writing, of the Licensing Authority defined in clause (b) of rule 21. This is mandatory before initiating any clinical investigation. It applies to all Subsequent New Drug clinical trials.
Phase-wise Clinical Trial Requirements: Human clinical trials (Phase-I), exploratory clinical trials (Phase-II), and confirmatory clinical trials (Phase-III) shall be conducted based on sequential data generation. Each phase requires submission in Form 44 with required fee and data under NDCT. This ensures proper evaluation at each stage.
Submission of Clinical Trial Data: The applicant shall submit data as given in Appendix I or Appendix IA or Appendix IB to NDCT including the results of clinical trials carried out in the country. Reports must be submitted in the format given in Appendix II. This data is essential for regulatory evaluation.
Requirement of Local Clinical Trials: Results of local clinical trials carried out in accordance with the guidelines specified in NDCT must be submitted. However, this requirement may be relaxed if the Licensing Authority decides based on data available from other countries in public interest. This ensures flexibility in approval.
Ethics Committee Approval and Registration: Approval of the Ethics Committee shall be obtained before initiation of the study. No Ethics Committee shall review and accord its approval without prior registration with the Licensing Authority. This ensures ethical conduct of trials.
Safety Monitoring and Compensation: In case of injury or death during Clinical Trial, free medical management shall be given. Financial compensation shall be provided, and the sponsor shall bear expenses. This ensures protection of trial subjects.
Compliance with Guidelines and Reporting: Clinical trial shall be conducted in compliance with approved protocols, NDCT, and Good Clinical Practice Guidelines. Serious adverse events must be reported within ten days. Annual status reports must also be submitted.
Registration and Oversight of Clinical Trials: Clinical trial shall be registered before enrolling the first patient. The Licensing Authority may inspect trial sites and review compliance.

These requirements ensure that all clinical trials conducted for Subsequent New Drugs are safe, ethical, and scientifically valid.

Conclusion

The concept of subsequent New Drug India ensures that any modification made to an already approved Drug is properly reviewed before marketing. Any change in indication, dosage, or formulation must be supported with adequate data. The regulatory pathway ensures step-by-step evaluation, while clinical trial requirements provide evidence for safety and effectiveness. Together, these processes help ensure that modified Drugs are safe, reliable, and suitable for patient use.

References

Central Drugs Standard Control Organization, Directorate General of Health Services, Ministry of Health and Family Welfare, Government of India. Frequently Asked Questions (FAQs) on New Drugs and Clinical Trials. Accessed April 13, 2026. https://cdsco.gov.in/opencms/resources/UploadCDSCOWeb/2018/UploadPublic_NoticesFiles/faqnd.pdf
SND. Accessed April 13, 2026. https://cdsco.gov.in/opencms/opencms/en/Drugs/Subsequent-New-Drugs
CDSCO. SND-Process-flow-chart-Formulation. Accessed April 13, 2026. https://cdsco.gov.in/opencms/export/sites/CDSCO_WEB/Pdf-documents/SND_pdfs/SND-Process-flow-chart-Formulation.pdf
SUGAM_user_manual. Accessed April 13, 2026. https://cdsco.gov.in/opencms/export/sites/CDSCO_WEB/Pdf-documents/SUGAM_user_manual.pdf
SND-Process-flow-chart-Formulation-Purely-subsequent. Accessed April 13, 2026. https://cdsco.gov.in/opencms/export/sites/CDSCO_WEB/Pdf-documents/SND_pdfs/SND-Process-flow-chart-Formulation-Purely-subsequent.pdf
Central Drugs Standard Control Organization, Ministry of Health and Family Welfare, Govt. of India. *THE DRUGS RULES, 19451. Accessed April 13, 2026. https://cdsco.gov.in/opencms/resources/UploadCDSCOWeb/2022/drug_rules/Drugs%20Rules,%201945.pdf