COWEN COLLABORATIVE INSIGHTS February 25, 2019 head on a surface). The primary efficacy endpoint of the trials was a comparison between Epidiolex and placebo in the percentage change in the monthly frequency of =a drop seizures during the 14 week treatment period (including 2 weeks of dose escalation) compared to the 4 week baseline period. Following the completion of the blinded portion of the trial, all patients were eligible to receive Epidiolex in an open label extension study. Figure 123 1st LGS Phase 3 Trial Design Figure 124 2nd LGS Phase 3 Trial Dose Ranging Design ‘ weeks «-——. 14 week analysis period ————+j Up to : —__—— 14 week analysis period ————+} cin, +> Auris | _—_ 22wmie,_ tn le Ee uo a — sau — | Has Period Phase Phase | Period ‘Observation | Titration Treatment Taper ; } se aero arma § : _ | Period «=| Phase Phase Period : 8 3 : a § Rancorniren ath 3 3 g f : | -LGS2:>210 patients randomized g : & s Placebo (nso) 5 6 3 3 — | 3 Epidiolex 10 mg/kg (n=50) 3 i i e : g a 2 -Dravet 2: enrollment ongoing uy Primary Endpoint: % change from baseline in monthly drop seizure frequency during & ie a Placebo (n=50) gS the 14 week treatment period compared with the 4 week baseline period 4 q Oo Measures taken to ensure quality, reduce noise include: ' 1 -Choice of primary endpoint -Daily IVRS -Diagnosis verification -Investigator selection of responsible -Seizure count and description training and familiar parents Source: GW Pharma Source: GW Pharma The first Phase Ill trial, patients were on an average of three AEDs, and had previously tried and failed an average of 6 other AEDs. Even on their baseline medications, the patients were experiencing a median baseline drop seizure frequency of 74 per month. The average age of patients in the trial was 15 years, although 34% were 18 years or older. On the primary endpoint, Epidiolex produced a median reduction in monthly drop seizures of 44% compared to a reduction of 22% in patients taking placebo (p=0.0135). Epidiol