( ( ( ( ( Two ( newly ( approved medicines ) ) ) , ) ( marketed ( under ( the ( brand ( names ( ( Relenza and ) Tamiflu ) ) ) ) ) ) ) , ) ( ( ( ( ( keep ( the ( influenza virus ) ) ) ( from ( ( spreading ( from cell ) ) ( to cell ) ) ) ) and ) ( have ( been ( ( shown ( in studies ) ) ( to ( reduce ( ( the ( ( severity and ) duration ) ) ( of ( flu symptoms ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (CD Two) (RB newly) (VBN approved) (NNS medicines)) (, ,) (VP (VBN marketed) (PP (IN under) (NP (DT the) (NN brand) (NNS names) (NNP Relenza) (CC and) (NNP Tamiflu)))) (, ,)) (VP (VP (VB keep) (NP (DT the) (NN influenza) (NN virus)) (PP (IN from) (S (VP (VBG spreading) (PP (IN from) (NP (NN cell))) (PP (TO to) (NP (NN cell))))))) (CC and) (VP (VB have) (VP (VBN been) (VP (VBN shown) (PP (IN in) (NP (NNS studies))) (S (VP (TO to) (VP (VB reduce) (NP (NP (DT the) (NN severity) (CC and) (NN duration)) (PP (IN of) (NP (NN flu) (NNS symptoms))))))))))) (. .)))
Two newly approved medicines, marketed under the brand names Relenza and Tamiflu, keep  the influenza virus from spreading from cell to cell and have been shown in studies to reduce the severity and duration of flu symptoms.
(ROOT (S (NP (NNP Tamiflu)) (VP (VBZ inhibits) (NP (NP (NN spread)) (PP (IN of) (NP (NN virus))))) (. .)))