Smoking is the leading preventable cause of death, and tobacco control professionals continue to make progress in cessation efforts. Pharmacists can assist smokers seeking to quit by offering counseling on smoking cessation pharmacotherapies. Pragmatic randomized trials are useful for investigating practical questions about an intervention's risks, benefits, and costs in routine clinical practice.To evaluate an enhanced pharmacy care (EPC) program involving personalized pharmacist-provided telephone counseling for supporting prescription smoking cessation medications compared with usual care (UC).Cigarette smokers filling a newly prescribed smoking cessation pharmacotherapy and with pharmacy benefits managed by Express Scripts were recruited. Qualified subjects were randomized 1:1 to EPC and UC. Subjects in EPC received 3 telephone-counseling sessions from specialist pharmacists during the early course of the study, while subjects in UC did not receive any counseling sessions. Study outcomes were collected through telephone contact and using the Express Scripts prescription database. The primary outcome assessed the 1-week point prevalence (PP) of smoking abstinence at the end of the trial (week 12). Secondary outcomes included 4-week PP at week 12 and adherence, evaluated by proportion of days covered (PDC), to prescribed smoking cessation pharmacotherapies.There were 1,017 randomized subjects. Among them, 1,002 subjects were included in the analysis, and 513 were randomized into EPC and 489 into UC. Baseline demographics, smoking history, and prescribed smoking cessation pharmacotherapies were comparable. Varenicline and nicotine replacement therapy (NRT) were most frequently prescribed for smoking cessation. In EPC, 46.0% received all 3 counseling sessions; 29.4% received 2 sessions; and 14.6% received 1 session. Overall, 353 subjects in EPC and 383 subjects in UC completed the week 12 assessment. In the analysis for 1-week PP of smoking abstinence at week 12, the percentage of abstainers in EPC was numerically higher than in UC (42.3% vs. 38.2%) with OR = 1.24, 95% CI = 0.96-1.61. It was not statistically significant. Adherence to prescription smoking cessation medication was significantly higher in EPC versus UC (49.7% vs. 45.6%; P = 0.033).This study evaluated whether a telephone-based pharmacy care program, provided by pharmacists and designed to support attempted quitters, improved quitting and increased adherence over usual care. The findings suggest that an enhanced program may benefit smokers by increasing prescription smoking cessation medication adherence. Future research should explore this program's effect on smokers who are compliant, based on insights on quitting provided by the post hoc analyses and limitations of the current study design.This study was sponsored by Pfizer. Gong, Baker, Zou, Bruno, Jumadilova, and Lawrence are employees and stockholders of Pfizer. Wilson and Ewel are employees of United BioSource Corporation, which received funding from Pfizer for conducting this study and for the development of this manuscript. Study concept and design were contributed by Gong, Bruno, and Ewel, with assistance from Jumadilova, Lawrence, and Zou. Gong, Jumadilova, Lawrence, and Ewel collected the data. Data interpretation was performed by Baker, Zou, and Wilson, assisted by Gong, Lawrence, and Ewel. The manuscript was written by Baker, Ewel, and Gong, with assistance from the other authors, and revised by Baker, Wilson, Zou, and Gong, with assistance from Bruno and Jumadilova.