In September, one of California’s largest private payers, Anthem Blue Cross, joined 7 Los Angeles health systems in a new managed care contract with savings and risks shared among the payer and health systems. In a state where premiums have increased at a rate 5 times faster than inflation over the past decade, the new partnership aims to slow spending through mutual price control and clinical coordination among the narrow network of prior rivals, while offering employers and individuals lower premiums and zero deductibles.