Question for EGM

I can't make the EGM, so if anyone is going and would be willing to ask the following question on my behalf I'd be greatful.

My understanding is that the strand of cowpox virus used in the vaccine to eradicate small pox had a higher rate of negative side effects including death, to those who were imunocompromised. Where does cf33 stand being from the same family of virus? If this is a possible trait of cf33, will this mean people on chemotherapy will not be able to use it in their imunocompromised state? How will the compatibility of cf33 and chemo be assessed without risking the trial?