I re-ran my DCVax-L Progression Free Survival (PFS) model with updated assumptions from last week's ASCO presentation.
My model now gives DCVax-L a 14 month mPFS vs 7 months for its placebo thereby providing a 6 month treatment advantage (measured from time of treatment). This trial requires a 4 to 5 month treatment advantage to demonstrate statistical significance.
Previously my model gave DCVax-L a 16 month mPFS vs 6 months for placebo. The main reason for my now lower estimated PFS number is that I increased the efficacy curve of the placebo arm. I made this change based on Dr Bosch’s statement at ASCO that ~90% of all trial patients have received DCVax-L treatment either upfront or at cross-over. Previously, around December 2016, Principle Investigator, Dr. Linda Liau stated 86% of patients have received DCVax-L treatment. So it can be inferred that during the past 6 months ~12 additional placebo patients may have experienced PFS events. It is possible Dr. Bosch's ~90% figure is the same as Dr. Liau's 86%, in this case the trial's chance of success improves significantly.
Changes to my modal -
* updated enrollment ramp numbers (extrapolated from ASCO slide)
* broke-down my K-M curve points into 6 month increments
* added 6 patients as Lost to Follow-up (LTFU)
* made Dec’16 the date 248 PFS events hit
* assumed 16 placebo had not evented at Dec’16
Highlights from ASCO presentation:
DCVax-L Program -
* Efficacy determination is made by a central review process
* 90% of pts received L (LL said 86%?)
* trial is powered both for PFS and OS independently
* ~3 month period btw screening and treatment
* pseudo progressors not mentioned in exclusion criteria
* 80-80% cell purity required to produce vaccine
* a few patients were lost to follow-up
* enrollment midpoint hit in May2014
* fully enrolled in November2015
* 231 pts have evented
* OS 233 event expected to be hit around mid July
* preliminary analysis publication of results is in the works
* 7 SAEs related to L or placebo
* 132 SAEs related to GBM or SOC
* SOC expected OS 15 -17 mths from diagnosis
DCVax-L Information Arm:
NWBO is in a very distressed financial state. The company has ~$6.5M debts due in late June. Investors may suffer substantial dilution when this debt is settled.
* Dr B said most indeterminate patients are probably rapids with a few pseudos (LL said the opposite)
* mOS of this group was 21.5 mths
* 24% > 48 mths OS
* 40% > 35 mths OS
DCVax-Direct Highlights:
* Sarcoma Phase2 trial to open in several months
* plan to expand this trial for pediatric patients
* Phase 2 trials to include CI in indications where they are approved already
* 7 of 8 PH1 sarcoma pts exceeded their expected survival times
* PH1 survival times 18% > 30 mths, 23% > 24 mths
* 59% exceeded their expected survival time by an average of 11 mths
* 4 SAEs
* Direct is manufactured in an automated system
Disclosure - I am long NWBO, I do not short stocks.
