The objectives of this publication are to 1 ) evaluate the effects of tapentadol ( NUCYNTA and NUCYNTA extended release [ ER ] ) on sex hormone concentrations in healthy male volunteers ( vs placebo and morphine ) and patients with osteoarthritis ( vs placebo and oxycodone ) , and 2 ) present a mechanistic hypothesis explaining how the combined MOR agonist and NRI activities of tapentadol may result in less impact on androgen concentrations .