Investigating the miracle biologic Lecanemab for Alzheimer's Disease - Part 6

Lecanemab’s modified intention to treat analysis should come with a warning

Another issue that bothered us in the TTE office in the Lecanemab Early Alzheimer's Disease trial was the use of the modified intention-to-treat population for the efficacy analysis.

Internal validity of clinical trials is the extent to which you trust the methods on which the results are based. There are some simple methodological issues, such as the presence or absence of randomisation, which allows you to understand whether the effect size is dramatically inflated due to differences in the baseline characteristics of the population.

Other essential methods, such as blinding, allocation concealment, and intention to treat, also affect the results. Now, bear with us while we explain one often confusing thing: the intention-to-treat analysis.

In an intention-to-treat analysis, the results are based on those initially assigned to the treatment and not just those who actually took the treatment (often referred to as per-protocol analysis). The intention to treat analysis mainly leads to sm…