Omeros Corporation: Additional Positive Data in Patients with Hematopoietic Stem Cell Transplant-Associated Thrombotic Microangiopathy


OMER logoOmeros Corporation (NASDAQ:OMER) announced further positive data from its ongoing Phase 2 study of OMS721 evaluating patients with hematopoietic stem cell transplant-associated thrombotic microangiopathy (HCT-TMA). Initial positive data from this study have been presented at the 2017 combined annual meetings of the Center for International Blood & Marrow Transplant Research (CIBMTR) and the American Society for Blood and Marrow Transplantation (ASBMT).

The Phase 2 protocol provides for patients to receive weekly OMS721 treatments for four or eight weeks, at the discretion of the investigator. To be eligible for enrollment, HCT-TMA patients are required to be adults with post-transplant TMA persisting at least two weeks following calcineurin inhibitor modification (conservative treatment). This population is at high risk for poor outcomes, including mortality. These patients often have severe co-existing conditions, and mortality rates have been reported to be as high as 100 percent.

A total of 14 HCT-TMA patients have been enrolled to date in the ongoing Phase 2 study. Eight patients have completed the protocol-specified treatment. Another four patients either withdrew consent or were discontinued by the investigator after only two to three weeks of treatment with OMS721. Three of the four patients for whom OMS721 treatment was discontinued early experienced deterioration of their conditions and subsequently died; the other patient, per protocol, was not followed and disposition is unknown. Two other patients are currently receiving OMS721 treatment.

Substantial and statistically significant improvements in markers of TMA activity, specifically mean platelet count, mean lactate dehydrogenase (LDH), and mean haptoglobin again were seen in this expanded number of study patients. At the end of protocol-allowed treatment, the mean platelet count (normal range: 150,000 – 400,000 x 106/mL) increased from 19,610 x 106/mL at baseline to 56,570 x 106/mL (p < 0.05). The mean LDH (normal range: 125-220 U/L) decreased from 624 U/L at baseline to 303 U/L (p < 0.01). The mean haptoglobin (normal range: 14-268 mg/dL) increased from 9 mg/dL at baseline to 134 mg/dL (p < 0.01). Mean creatinine remained stable at approximately 120 mmol/L (normal range: 63-104 mmol/L) but a large majority of patients had co-existing conditions for which they were receiving nephrotoxic medications. Other serious co-existing conditions included graft versus host disease (GvHD), cytomegalovirus and human herpes virus 6 infections, prior sepsis, hemorrhagic alveolitis, and residual underlying malignancies.

OMS721 has been well tolerated and no safety concerns have been identified. The most commonly reported adverse events were diarrhea and nausea.

Two HCT-TMA case reports have also been presented. One patient was an adolescent girl who did not tolerate eculizumab treatment, but responded well to compassionate use OMS721 treatment. She was able to discontinue hemodialysis as well as platelet transfusions that she required daily when first treated with OMS721. Her case was presented by her treating physician last March at the 43rd Annual Meeting of the European Society for Blood and Marrow Transplantation (EBMT).

The second was a study patient who had a difficult post-transplant course, including steroid-resistant GvHD and cytomegalovirus infection. He developed TMA that did not respond to conservative measures and had co-existing GvHD with multiple neurological complications and was unable to walk. Following OMS721 treatment, his TMA and GvHD resolved and his neurological complications improved. He was able to walk and has been discharged in stable condition. His neurological status has continued to improve. This patient was reported last week at the EBMT Crash Course on Diagnosis and Treatment of Noninfectious Complications after HCT.

“Patients with stem cell-associated TMA continue to show robust improvement when treated with OMS721,” stated Gregory A. Demopulos M.D., chairman and chief executive officer of Omeros. “These are complex patients with severe co-morbidities and high mortality rates with no approved treatment option, and yet OMS721 has consistently managed their TMAs and also appears to improve GvHD, a frequent and deadly complication of TMA. We look forward to working with global regulatory agencies to start our OMS721 Phase 3 clinical trial in patients with HCT-TMA.”

While Omeros collects additional data through continued enrollment of the Phase 2 TMA study, the company is preparing to initiate an OMS721 Phase 3 clinical trial in patients with HCT-TMA and, for this indication, is pursuing FDA’s breakthrough therapy designation and the European Medicines Agency’s Priority Medicines (PRIME) status. For IgA nephropathy, OMS721 already has received breakthrough therapy designation from FDA and is also applying for PRIME status. Phase 3 clinical programs are in progress evaluating OMS721 in both IgA nephropathy and atypical hemolytic uremic syndrome.

Shares of Omeros are currently trading at $14.16, down $0.58 or -4%. OMER has a 1-year high of $27.09 and a 1-year low of $7.80. The stock’s 50-day moving average is $20.40 and its 200-day moving average is $19.52.

On the ratings front, OMER stock has been the subject of a number of recent research reports. In a report issued on October 20, Maxim analyst Jason Kolbert assigned a Buy rating on OMER, with a price target of $24, which implies an upside of 61% from current levels. Separately, on August 24, Cantor’s Elemer Piros reiterated a Hold rating on the stock.

According to TipRanks.com, which ranks over 7,500 financial analysts and bloggers to gauge the performance of their past recommendations, Jason Kolbert and Elemer Piros have a yearly average loss of -7.7% and a return of 4.7% respectively. Kolbert has a success rate of 35% and is ranked #4622 out of 4700 analysts, while Piros has a success rate of 46% and is ranked #1365.

Omeros operates as a biopharmaceutical company committed to discovering, developing, and commercializing small-molecule and protein therapeutics for large market as well as orphan indications targeting inflammation, coagulopathies and disorders of the central nervous system.