NorthWest Biotherapeutics Inc (NWBO)

[Dr Bala]

From JAMA. No big deal.

Many trials, especially for incurable diseases, incorporate a
crossover design for feasibility and/or ethical reasons. A crossover
was considered necessary when our study began in 2007
to make patient enrollment and retention feasible when novel
immunotherapies were not yet generally viewed as promising
for cancer. The crossover was also important to justify the placebo
group for patients undergoing a leukapheresis—an invasive procedure
necessary for blinding and for manufacturing vaccine
but offering no benefit to patients in the placebo group if
they could not receive their autologous vaccine.