Frrol, Reasonable points you have brought up but, I would question to a degree the conclusions you draw.
First in the P2 for the use of Opdivo in advanced bladder cancer the 19.6% response rate was only slightly above the traditional secondary chemotherapy response rate of 10-15%. We can argue whether 5 to 10 percent is statistically significant efficacy however I will give you that to the additional responders it was important. We could also quibble about what 2-73 has shown in efficacy but the 20% "super responders and the demonstrable improvement across the remaining participants proves "some statistical significance". The FDA granted approval after the Opdivo P2 because it could extend and possibly save lives in a small population of patients who faced a death sentence with the disease. This will be the same logic for 2-73's use for Alzheimer's patients who face an equally deadly but more protracted disease. I think this is being evaluated by FDA's CDER as we speak.
Secondly, Immunotherapy is in its infancy and much research is yet to be accomplished about the MOA of Immune Checkpoint drugs. There is a fine line between effectively using these drugs to spur the immune T-cells into action to attack disease and keeping the immune system from attacking other healthy parts of the body.. So I question the statement that, "Their MOA was clear and proven" (see below). On the other hand, there is a lot of research cited on this board which delves into the Sigma 1 MOA and I believe ANAVEX will eventually clearly prove it.
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This study of nivolumab (Opdivo) has some limitations, Dr. Apolo noted. For example, because it was a single-arm study, the efficacy of nivolumab was not compared directly with that of another treatment. In addition, the accelerated approval was based on the objective response rate, the study’s surrogate endpoint.
“The clinical benefit, as reflected by the surrogate endpoints, should be verified or established in a randomized clinical trial,” Dr. Apolo said. Currently, there is an ongoing randomized trial testing nivolumab versus placebo in patients who have undergone surgery to have their bladder tumor removed.
However, because there are so few treatment options for patients with metastatic bladder cancer who do not respond to chemotherapy, some physicians began treating patients with nivolumab as soon as preliminary results from the phase II trial were reported at an oncology meeting in 2016. Now that the FDA has approved the treatment, health insurance is more likely to cover its cost, explained Dr. Apolo.
