The theory of Rational Addiction

The Theory of Rational Addictions, by Gary Becker & Kevin Murphy (1988), was a rational choice model that became a standard tool for economists modeling addictive behavior. The approach differs from other theories of addiction by modeling addictive behavior as the gradual implementation of a rational, forward‐looking plan, where consumption at any point in time is partly motivated by the immediate payoff of consumption and partly by the effects this consumption has on the individual in the future. This makes addictive behavior a subset of rational behavior, requiring no more specific government policies or attention than any other consumption choice. Later work by economists extended the theory in different ways, allowing it to match an increasing number of consumption patterns, and searched for ways to test the forward‐looking assumption in different types of market data. While the work was successful as a contribution to rational choice theory, with possible statistical applications, there are several reasons to dismiss its usefulness as an explanation of real‐world addictive behavior and its ability to assess the welfare effects of addictions.     

Pembrolizumab After Two or More Lines of Previous Therapy in Patients With Recurrent or Metastatic SCLC: Results From the KEYNOTE-028 and KEYNOTE-158 Studies

IntroductionPembrolizumab has shown clinical benefit in patients with previously treated recurrent or metastatic SCLC in the phase 1b multicohort study KEYNOTE-028 (NCT02054806) and the phase 2 multicohort study KEYNOTE-158 (NCT02628067). We present a pooled analysis of patients from KEYNOTE-028 and KEYNOTE-158 who had received two or more lines of previous therapy for SCLC.MethodsEligible patients were aged 18 years and above, had histologically or cytologically confirmed incurable recurrent or metastatic SCLC, had an Eastern Cooperative Oncology Group performance status of 1 and below, and had received two or more lines of previous therapy. Patients in KEYNOTE-028 were required to have a programmed death ligand 1 (PD-L1)–positive tumor. Patients received pembrolizumab (10 mg/kg every 2 weeks in KEYNOTE-028 or 200 mg every 3 weeks in KEYNOTE-158) for up to 2 years. The primary end point was objective response rate per Response Evaluation Criteria in Solid Tumors version 1.1, which is presented here per independent review.ResultsEighty-three patients who had received two or more lines of previous therapy (KEYNOTE-028, n = 19; KEYNOTE-158, n = 64) were included. Median follow-up duration was 7.7 (range, 0.5–48.7) months. Objective response rate was 19.3% (95% confidence interval: 11.4–29.4); two patients had complete response (one with a PD-L1–positive tumor), and 14 patients had partial response (13 with PD-L1–positive tumors). The median duration of response was not reached (range, 4.1‒35.8+ mo; plus sign indicates ongoing response); 61% of responders had responses lasting 18 months or longer. Fifty-one patients (61.4%) experienced any-grade treatment-related adverse events; eight patients (9.6%) had grade 3 or higher events.ConclusionsPembrolizumab exhibited durable antitumor activity in a subset of patients with recurrent or metastatic SCLC who had undergone two or more previous lines of therapy, regardless of PD-L1 expression. Pembrolizumab was well tolerated.