Replies to post #163451 on Biotech Values

[DewDiligence]

(JNJ)—PTLA does not have the only FXa-antidote; in this trial, JNJ used prothrombin complex concentrates (a standard product from plasma-collection companies) to reverse the effect of Xarelto:

http://finance.yahoo.com/news/prothrombin-complex-concentrates-reverse-blood-070000363.html

The study, presented today as an oral session at the International Society on Thrombosis and Haemostasis Annual Meeting in the Netherlands, evaluated three- and four-factor PCCs in 34 healthy adults treated with 20 mg of XARELTO. Participants were treated with XARELTO twice a day for four days. On the fifth day, participants received either a 50 IU/kg single bolus dose – quickly administered intravenously – of three-factor PCC (Profilnine SD), a four-factor PCC (Beriplex P/N), or a 100 mL single bolus dose of saline as a control.

Both three- and four-factor PCCs were found to partially reverse the XARELTO®-induced prolongation of the prothrombin time (PT) – the time it takes the blood to clot – in healthy subjects, with the latter reducing the mean PT by 2.5 to 3.5 seconds (versus a 0.6 to 1.0 second reduction associated with three-factor PCC). Conversely, three-factor PCC had a greater effect on the reversal of XARELTO®-induced changes in endogenous thrombin potential (ETP) – the total amount of thrombin generated during the test – than four-factor PCC.

Based on my interpretatin of this PR and the one from PTLA in the preceding post (#msg-89623120), PCCs are not quite as effective as PTLA's PRT-4445.

Perhaps JNJ is running the study of PCCs to increase its negotiating leverage with PTLA for a PRT-4445 development deal.

[DewDiligence]

PTLA starts phase-3 trial of andexanet alfa (PRT4445) as Eliquis antidote:

http://finance.yahoo.com/news/portola-pharmaceuticals-initiates-phase-3-120000659.html

In the first part of the study, approximately 32 healthy volunteers will be given Eliquis 5 mg twice daily and then randomized in a 3:1 ratio to andexanet alfa administered as a 400 mg IV bolus or to placebo. In the second part of the study, approximately 32 healthy volunteers will be randomized in a 3:1 ratio to andexanet alfa administered as a 400 mg IV bolus followed by a continuous infusion of 480 mg at 4 mg/min for 120 minutes or to placebo. Study participants will be followed for up to 43 days to assess safety.

The PR headline says this trial is under the Accelerated Approval pathway, but I wouldn’t interpret that as a binding commitment by the FDA to grant AA if the study results are positive.