This date is projected using the known KM curve for the SOC group. Now with 159 people in trial (4/31/08) and 33 more estimated to date, I made the FALSE assumption all were under SOC. Under this situation of the 51 enrolled from start in early 2005 until 11/15/2006, I assumed 90% or 45.9 people had died. Of 53 people enrolling from 11/16/06 to 7/31/07 I assumed 75% or 39.8 are dead. 14 people from 8/01/07 to 10/31/07 30% or 4.2 have died. 41 people from 11/1/07 to 4/31/08 20% or 4.1 people have died. Of 33 people since 5/1/08 (my low ball guess), 7% or 2.3 have died. TOTAL DEAD: 96.4 as of 8/1/08. Backtracking I'll use 7/15/2008 as the 92nd event if everyone was on SOC.
Now if TNFerade is to be a viable product I would like to see a 4 month improvement over SOC. 4 months = 120 days. Since the TNF arm is 2/1 over SOC, I multiply 120 by .666 and get 80 days. That gets me to October 5, 2008. Probably just before noon.
Sorry to drive all you statisticians crazy with this "logic". If someone has a better date lets hear it. Regards, Steve
This is how it is likely to play out. Any comments are welcome.
In earlier data, TNF+Standard-of-care has shown essentially the same survival rate as Standard-of-care for patients that were either treated recently (patients enrolled < 11 months ago) or treated long ago (patients enrolled > 24 months ago). TNF+SOC shows higher survival chances than SOC only in the middle (patients enrolled 11 months – 24 months ago), so we can try to estimate (with several assumptions) on how much better TNF+SOC might be than SOC in that time period, given the fact that 92 event mark was reached in end-Aug.
Using known survival curve for SOC, and looking backwards from end of August 2008 (when 92 deaths were reached),
• Roughly 58 patients had been enrolled < 8 months ago. Assuming 2% trial dropout and 10% death rate for both TNF+SOC and SOC (as shown in earlier trial data), this would have likely led to 5.7 deaths
• Roughly 17 patients had been enrolled 8-11 months ago. Assuming 3% trial dropout and 30%-40% death rate for both TNF+SOC and SOC (as shown in earlier trial data), this would lead to 4.9 likely deaths
• Roughly 43 patients had been enrolled >24 months ago. Assuming 10% trial dropout and 90% death rate for both TNF+SOC and SOC would lead to 36.8 likely deaths
So total dead amongst patients treated recently or long ago = 47.4
Roughly 71 patients were enrolled in middle between 11-24 months ago. Assuming 5% trial dropout, 22 of participating patients would be on SOC and 45 on TNF+SOC. If we assume SOC patients had 75%-80% death rate (very realistic given earlier data), we would need to have likely achieved 55-65% death rate amongst TNF+SOC patients so that all deaths add up to 92.
Based on plugging several iterations of these several assumptions, my best guess is that upcoming data in next few days will show that TNF+SOC achieves 40-45% survival (versus 20-25% survival on SOC alone) in patients that were enrolled between 11-24 months ago, and no statistical advantage either in patients early into treatment (enrolled <11 months ago) or late into treatment (enrolled > 24 months ago). Even though interim data had earlier shown a 8+ month improvement in median survival, the upcoming data will show < 4 month improvement in median survival so GenVec would likely try to use 18 month or 24 month survival rate as a key efficacy end point.
Where do you get your data from for patients in both arms treated for more than 24 months? You stated that the survival rate will be the same for both. It is my belief that the TNFerade arm will have superior survival results for patients in the PACT study for more than 24 months.
I promised myself I was going to stop running numbers because all I was accomplishing was driving myself crazy with all the possiblities.
However, as I was driving today...something on Newby's projection of 10/5/2008 hit me.
His calculation was based on a 4 month (120 day) benefit showing on the first 92 dead. PACT is desinged for Overall Survival and the benefit will be in the living.
Yes, plain SOC should be dying off
Some TNFerade patients will be dying off as well and may not show a large benefit..but this should be normal as well. Not eveyone will benefit the same.
The real benefit should be showing up in the living !
So could this be a flaw in Newby's projection ???
Anyone feel free to correct my conjecture.
A graph of survival times presented at the annual meeting indicated a skewed distribution of survival times. The new data on PC will presumably provide a better handle on that distribution. I speculate that, as endoscopic techniques are improved, the long-term survior percentage will increase. Thus, I continue to be optimistic about this drug, especially for other indications where administration would seem to be easier.
ALTH phase 2 with SPA
Interesting that Wall St snapped up 10 million shares of ALTH last quarter.
Also interesting is that the stock trended down durning most of the accumulation period.
Right now...most of Wall ST is in the show me the money phase. A decent look in Q4 will start some interest..the look at 184 should have things really cooking.
Management closing a partnering deal wouldn't hurt either.
To quote Winston Churchill:
We may be at the end of the beginning.
(PACT second look)
ALTH had $100MM in cash as of 6/30/08. Lead compound is being tested under SPA with 3rd (and possibly final) look expected end of this year. First TWO looks were VERY positive, so if results at end of year meet SPA, approval is extremely likely in `09. Not limited to localized cancer, small molecule therapy (i.e. no unusual route of administration).
Cash + excellent 1st/2nd looks + SPA + next (final?) look Dec 08 + no ROA issues ... possible approval early `09
IMO, given the subjectiveness of the market, these differences alone could explain premium over GNVC