p <- list("CL" = CL_VAN, "V" = V_1)
r <- new_regimen(amt = dose, times = ordered_time, type = "infusion", t_inf = infusion_duration)
dat <- sim_ode(ode = pk_1, par = p, regimen = r, only_obs = TRUE, obs_step_size = .01666, t_max = max(data.6502944$rt))