Substantial amendments can only be applied for after approval of the clinical study protocol. Within 35 days from the validation of the application for a substantial amendment, a decision letter is sent to the sponsor. The proposed changes can only be implemented after approval of the substantial amendment.
A short guide on the classification and the assessment of substantial amendments at the Medical Products Agency is provided in the right hand column.
For more detailed information consult Directive 2001/20/EC and Detailed guidance on the request to the competent authorities for authorisation of a clinical trial on a medicinal product for human use, the notification of substantial amendments and the declaration of the end of the trial (2010/C 82/01).