FYI, here are the two only available immunotherapy phase 3 trials on BTC so far (according to Merck's Lancet paper 2023), and hence, the two only immunotherapy drugs got FDA green light on BTC. Just from the number, neighter one is outperforming the other and both can not provide a chemo free option on this cancer type.
From the available numbers, even the ORR and DCR came good at the beginning, there are very big drops in both trial in the 12month responding rate and correspondingly, big drops in the 24month survival rate. This clearly speaks to the antibody drug resistance and the relapse in responding, which are pretty big issue for immunotherapy these days.
For fun only here, just to speculate the potential of CF33 to become an attractive asset to a BP by the trial expension (extra 10-
20 pts),
1. For BTC patients, this is the
first and only 'maybe' as a
chemo free option to go forward and more importantly, this might be a
mono therapy, not having to reply on anyone else
2. Might look for a high ORR number of over 50% to outperform any other agent.
3. This is covering all patient cohort, not like the many other current targeting therapy, focusing on FGFR mutation on BTC.
4. Hope for a long durable responding profile. Hopefuly, if close to 50% patients responding, they all respond for over 12months or longer, of which profile pushes final survival much better. (By the responding chart published so far, the higher dosed patients seemed going towards that way. We will see for it.)
5. (Not sure whether this one is very scientific. Without much literature to support.) For a patient relapsed from PD-1/PD-L1 treatment, it is very unlikely they will be responding to the same antibody drug again. However, for a patient recieves the oncolytic virus and relapses, particularly this CF33, highly infectious to tumor cells and replicable, I think the patient will have a good chance to see responding again with the same virus. Simply like you got cold flu last year, this year, hard to think you are not gonna get it next year. So CF33 by its nature, is working based on the tumor metabolic specific actions, independent from any particular marker from the body, this is more likely to successfully infect cancer cells and to work again in the body.
Aha, it is
Keynote-966
(20min delay)