Regulatory Decision Summary for DaTscan

The diagnostic efficacy of DaTscan in adult patients with suspected Parkinsonian Syndromes (PS) to distinguish between PS and essential tremor, was demonstrated in Study PTD304 with a specificity of 97% and sensitivity of 78%, and supported by Study DP008-003 which demonstrated high sensitivity (92.4% to 96.8%) and specificity (80.6% to 96.8%) of DaTscan to distinguish between PS and non-PS conditions in patients with clinically established diagnoses. The clinical benefit of DaTscan is to rule out PS in clinically uncertain cases.

The overall safety data indicate that DaTscan is generally safe and well tolerated. The safety profile of DaTscan is consistent with that of other diagnostic radiopharmaceuticals, in that the incidence of adverse events (AEs) is low, most AEs are mild, and the most common adverse reactions are hypersensitivity and injection site reactions. Appropriate warnings and precautions are included in the DaTscan Product Monograph. Interactions with commonly used medications are of concern for DaTscan due to the possibility of interference with DaTscan uptake in the striatum which may result in incorrect interpretation of images. Withholding such medications would also pose a risk to the patient, therefore the benefit and risk of administering DaTscan must be weighed in these situations.