From DNA to NDA--the impact of recombinant DNA technology on new drug development.

Man's long-standing efforts to alter living things through genetic manipulation have become reality. Recent advances in recombinant DNA technology have the potential to alter the drug-development process profoundly. The pharmaceutical industry has had to adjust its research efforts and develop new state-of-the-art laboratories.

Analgesia, plasma levels, and dosage of propoxyphene.

It can be shown that both the mean plasma levels observed and the mean analgesic scores (effectiveness) are related to the dose of an orally effective analgesic agent, although wide individual variations exist. Based on the pharmacokinetic characteristics of propoxyphene, it can be predicted and confirmed that equilibrium (or steady state) plasma levels will be achieved after about six doses when administered on a q. 6h.

Problems and solutions to single-dose testing of analgesics: comparison of propoxyphene, codeine, and fenoprofen.

Discrepancies exist between reports arising from single-dose and multiple-dose studies intended to compare the efficacy of oral analgesics. D Differences in the pharmacokinetic characteristics of these drugs account for much of the discord. Codeine and fenoprofen rapidly achieve their ultimate plasma equilibrium levels (on a q.