AMAG Pharmaceuticals said today it has agreed to acquire Perosphere Pharmaceuticals for up to $415 million, in a deal that the buyer said will expand its pipeline, and especially its presence in hematology with Perosphere’s next-generation anticoagulant reversal candidate ciraparantag (PER977).
Ciraparantag is an intravenously-administered synthetic small molecule anticoagulant reversal agent that according to Perosphere is believed to reestablish the body’s ability to form clots by binding to novel oral anticoagulants (NOACs) such as Bayer/Jansen Pharmaceutical (Johnson & Johnson)’s Xarelto® (rivaroxaban), Bristol-Myers Squibb/Pfizer’s Eliquis® (apixaban), and Daiichi-Sankyo’s Savaysa® (edoxaban), as well as to Sanofi’s Lovenox® (enoxaparin sodium injection), a low molecular weight heparin.
Ciraparantag is under study in patients treated with NOACs or low molecular weight heparin, when reversal of the anticoagulant effect of these products is needed for emergency surgery, urgent procedures, or due to life-threatening or uncontrolled bleeding. Ciraparantag has been granted the FDA’s Fast Track review designation and has patent protection through 2034.
“AMAG has been searching for a novel hematology asset to complement our existing portfolio and to leverage the expertise of our high performing Feraheme® hematology team,” AMAG president and CEO William Heiden said in a statement. “This acquisition represents a great strategic fit and a unique opportunity to add an innovative, durable, and differentiated mid-phase clinical asset to our portfolio.”
AMAG cited Perosphere’s Phase IIb clinical trials in which ciraparantag was administered to healthy volunteers after achieving steady blood concentrations of Eliquis (NCT03288454), Xarelto (NCT03172910), Savaysa (NCT01826266), and Lovenox (NCT02206100). In these studies, the company said, ciraparantag showed complete and sustained reversal of the anticoagulant effect of each drug studied by normalizing whole blood clotting time (WBCT), an important laboratory measure of clotting capacity.
In the trials, subjects experienced a rapid and statistically significant reduction in WBCT one hour after the administration of each of the three NOACs studied, as well as LMWH compared to placebo and the effect was sustained for 24 hours, AMAG said—adding that to date, the most common adverse events related to ciraparantag were mild sensations of coolness, warmth or tingling, skin flushing, and alterations in taste.
Promising Clinical Data
“Based on its attractive product characteristics and promising clinical data, we believe it has the potential to positively impact patient care in this rapidly growing patient population,” added Julie Krop, M.D., chief medical officer and EVP of development at AMAG. “We look forward to working with the FDA to confirm the design of our Phase III program, which is expected to include a Phase IIIa trial in healthy volunteers followed by a Phase IIIb/IV trial in patients.”
The transaction is expected to close in the first quarter of 2019, subject to customary closing conditions. At closing, AMAG agreed to pay Perosphere equity holders $50 million (subject to customary adjustments), and assume $12 million under a term loan and up to $6.2 million of Perosphere’s other liabilities. AMAG was issued a $10 million convertible note from Perosphere as part of an exclusivity arrangement, with those proceeds to be offset from up-front consideration at closing.
Perosphere equity holders will be eligible to receive up to $140 million in payments tied to achieving regulatory milestones, based on a final label with no boxed warning in the U.S. That figure includes a $40 million milestone payment tied to approval by European regulators.
Equity holders of Perosphere will also be eligible to receive up to $225 million in payments tied to achieving sales milestones. The first commercial sales milestone payment of $20 million would be payable upon achieving annual net sales of $100 million, AMAG disclosed.
The Phase III program will be partially funded by an existing agreement with an undisclosed global pharmaceutical company “which does not currently have commercialization rights to ciraparantag,” provided certain clinical milestones are met, AMAG stated.
As part of the Phase III program, AMAG said it plans to use a bedside coagulometer, currently being developed by Perosphere Technologies.
AMAG said the costs it expects to incur in 2019 toward advancing ciraparantag will not change AMAG’s preliminary projection for next year of negative adjusted EBITDA of approximately $50 million, which the company disclosed on November 1. AMAG added that it plans to issue 2019 guidance in early January.