Cigarette Consumption After switchinG to High or Low Nicotine strENght E-cigaretteS In Smokers With Schizophrenia

Multicenter, 12-months prospective trial, utilizing a randomized, double-blind, 2-arm parallel, switching design to compare effectiveness, tolerability, acceptability, and pattern of use between high (JUUL 5% nicotine) and low nicotine strength devices (JUUL 1.7% nicotine) in adult smokers with schizophrenia spectrum disorders. The study will take place at 5 international sites: UK (London), Italy (Catania), Russia (Ufa and St. Petersburg) and Ukraine (Kiev). The two devices have identical appearance and will be assigned in a double-blind fashion. Study products will be provided for a total of 6-months (intervention phase); the intervention phase will be followed by a further 6-months observational period (follow-up phase) during which no products will be dispensed to participants. Throughout the follow-up phase and up to the final visit at 12-months, changes in smoking/vaping behavior and in their pattern of use will be tracked under naturalistic condition and compared between study groups. Any changes in symptom severity related to schizophrenia spectrum disorders within and between both arms of the study will be monitored. The intervention phase of the study will consist of a total of nine visits (including screening). The follow-up phase will consist of three additional visits (two telephone contacts and one final face to face visit). In summary, the main objectives of the study will be to: 1. Quantify the proportion of continuous quitters among participants at 6-months in both arms of the study; 2. Quantify the proportion of continuous reducers among participants at 6-months in both arms of the study; 3. Quantify the proportion of continuous quitters among participants at 12-months in both arms of the study; 4. Quantify the proportion of continuous reducers among participants at 12-months in both arms of the study; 5. Compare continuous quit and reduction rates between study arms at 6- and 12-months; 6. Quantify adverse events throughout the whole duration of the interventional phase of the study in both arms; 7. Compare adverse events between study arms. Additional objectives of the study will be to: 1. Measure Subjective perceptions and experiences of the two nicotine strenghts by the psychometrically validated modified Cigarette Evaluation Questionnaire - mCEQ (at 6-months); 2. Compare level of mCEQ between study arms (at 6-months); 3. Assess pattern of products use among participants throughout the whole duration of the study (both at intervention + follow-up phases) in both arms of the study; 4. Compare pattern of product use between study arms (both at intervention + follow-up phases). 5. Compare changes in symptom severity of patients with schizophrenia by Positive and Negative Syndrome Scale (PANSS) within and between both arms of the study (both at 6- and 12-months); 6. Compare changes in exercise tolerance by Chester Step Test within and between both arms of the study (only at 6-months); 7. Compare changes in weight/BMI within and between both arms of the study (both at 6- and 12-months); 8. Quantify self-rated mental health (SRMH) throughout the whole duration of the study (by means of a specifically designed APP) within and between both arms of the study (both at 6- and 12-months).