Weight correction is justified when using Dosage unit Content uniformity to demonstrate Blend uniformity, for example when blend sampling presents severe risks to the operators taking the samples. CGMP (21 CFR.211.110) requires an in-process testing of powder blends to demonstrate adequacy of mixing. For stratified In-Process Dosage Unit Sampling (for example 20 units x 3 samples = 60 samples sampled during compression) for demonstrating dosage uniformity in validation batches (Process qualification) and for batch release testing (USP<905> Uniformity of dosage units) weight correction is not justified. Weight corrected content uniformity reflects uniformity of powder blend. At dosage unit stage (e.g. tablets), the content uniformity data should reflect overall variability due to powder blend plus the variability in dosage units (for example caused due to compression process in tablets). Hence it should be non weight corrected content uniformity
Weight correction is justified when using Dosage unit Content uniformity to demonstrate Blend uniformity, for example when blend sampling presents severe risks to the operators taking the samples. CGMP (21 CFR.211.110) requires an in-process testing of powder blends to demonstrate adequacy of mixing. For stratified In-Process Dosage Unit Sampling (for example 20 units x 3 samples = 60 samples sampled during compression) for demonstrating dosage uniformity in validation batches (Process qualification) and for batch release testing (USP<905> Uniformity of dosage units) weight correction is not justified. Weight corrected content uniformity reflects uniformity of powder blend. At dosage unit stage (e.g. tablets), the content uniformity data should reflect overall variability due to powder blend plus the variability in dosage units (for example caused due to compression process in tablets). Hence it should be non weight corrected content uniformity
Refer also: Blend Uniformity and Content Uniformity (BUCU) FAQsÂ