Amgen purchased Biovex at a valuation of $1B. Amgen did not actually pay $1B up front. I believe it was about 420 million up front and the rest in milestone payments. This is simply the nature of biotech deals. A portion is paid up front, then when certain miletones are hit the rest follows. To omit the milestone promises from the valuation total would be deficient and misleading. Look at the "title" of the Wall Street Journal article which covered the buyout. (e.g. "Bought for $1B.)
In immunotherapy trials, investigators are seeing very consistent results between Phase 1, 2 and 3. You can go compare Yervoy and PD1 phase 2/3 results with earlier Phase 1. You will see for yourself that the ORRs and CRs are basically the same (providing for rounding error due to sample size). This pattern is also clearly seen in ONCS Phase 1 and Phase 2 trial results. This consistency was not commonly reproducible with the older targeted agents and chemo drugs. Why? Most likely because of the PATHETIC efficacy of older drugs. Weak efficacy led to investigators trying to game the system. They would try to select only the "healthier" patients - those who weren't about to die. They could game this in Phase 1 and 2, but in Phase 3 the true efficacy would come out.
A second very important difference is that these older cytotoxic and pathway inhibitors attacked the cancer directly. The problem is this quickly selects for cancer cells that are not affected by that drug. So, a common observation was that patients might experience initial shrinkage of their tumors, but the OS (overall survival) was NOT improved. Tumors would shrink, and patients experience maybe 1 or 2 months of improved PFS (progression free survival). Meaning their cancers stopped growing for a few weeks/months. But when the cancer returned, it grew even faster and the patients, on average, died within the same amount of time.
For immunotherapy, things are very different. In many of these trials, patients had failed multiple prior chemo regimens. More importantly, it is very difficult to game the immune system. You either succeed in getting the immune system to work, or you don't. If it works, it tends to work in predictable fashion. Furthermore, responses tend to be far more durable than many of the older cytotoxics. The fundamental difference is that the older failed extrapolations involved drugs that attacked the cancer directly. In contrast, immunotherapy empowers the immune system to attack the cancer. The immune system is adaptive and it is much harder for the cancer to "escape". This is how you get patients with years-long durable complete regressions with only a few PD1 infusions performed years ago.
The indisputable fact is that the pharmaceutical industry and medical community has voted with BILLIONS of dollars and resources to focus on PD1 instead of Yervoy. This is not just because of superior toxicity, but significantly superior efficacy.
While it obviously remains to be seen of Tvec+PD1 would be superior to Tvec+CTLA4, the risk is more to the upside (that PD1 will work better than Yervoy). If Amgen KNEW for sure that PD1 is better than Yervoy, there would be no risk, and ONCS would not be $100m, but far closer to the $1B today. Hence the time to "place your bets" is obviously right now. Amgen has done so. Otherwise, with the superb Phase 1/2 Tvec+Yervoy results, why didn't they move on to Phase 3?? Why would they instead choose to switch to Tvec+PD1? The answer is obvious.
