DM199 shows promise in phase 2 trial for treating preeclampsia

DM199 shows promise in phase 2 trial for treating preeclampsia | Image Credit: © Egor - © Egor - stock.adobe.com.

DM199 (rinvecalinase alfa; DiaMedica Therapeutics) has shown positive results for treating preeclampsia in part 1a of a phase 2 clinical trial, according to DiaMedica Therapeutics Inc.¹

The therapeutic potential of DM199 was highlighted through meeting the safety and efficacy endpoints of the study. These included significant dose-dependent reductions in both systolic blood pressure (SBP) and diastolic blood pressure (DBP), alongside no placental transfer and no serious adverse events linked to the drug.

“With hypertension being the leading cause of delivery, often prematurely, in early onset preeclampsia, DM199’s ability to safely reduce blood pressure represents an exciting development in the search for an effective treatment for preeclampsia,” said Cathy Cluver, PhD, principal investigator of the trial and leader of the Preeclampsia Research Unit at Tygerberg Hospital.

If approved, DM199 will fill a gap for pharmacological treatments to manage preeclampsia in the United States. The trial is an open-label, single center, proof of concept study determining the safety and efficacy of the drug, planning to enroll up to 90 women with preeclampsia and up to 30 with fetal growth restriction (FGR).

Addressing an unmet medical need

Participants were aged a mean 32.5 years and enrolled at a mean 37-weeks’ gestation. At baseline, mean SBP and DBP were 165 mm Hg and 102 mmHg, respectively. DM199 was administered through an infusion, with additional SBP and DBP measurements performed after 5 and 30 minutes. Finally, measurements were taken at 24 hours after infusion.

The most significant reductions in SBP and DBP were observed among patients receiving the highest dose of DM199, at -35 mmHg and -15 mmHg, respectively. In pooled cohorts, significant reductions in mean blood pressure were found from the potentially therapeutic dose range at 5 minutes, 30 minutes, and 24 hours post-infusion.

For SBP, mean reductions were -25 mmHg, -15 mmHg, and -20, mmHg, respectively. For DBP, mean reductions were -13 mmHg, -13 mmHg, and -10 mmHg, respectively. This highlighted a durable response over time.

Safety profile and blood flow findings

Positive safety findings were also confirmed. All treatment emergent adverse events were mild, and included nausea in 14% of patients, headache in 11%, and flushing in 4%. No participants discontinued treatment or experienced induction of early labor.

A statistically significant reduction in pulsatility index (PI) measures was also observed in patients taking DM199, including a 13.2% mean reduction in blood flow resistance after 2 hours. This indicated improved uterine artery blood flow and placental perfusion, which may support fetal growth and potential disease modification.

The study population included 9 vaginal deliveries and 16 cesarean deliveries, with approximately 80% of deliveries occurring within 24 hours after enrollment. Following the positive results, a dose expansion cohort will be enrolled for additional phase 2 investigation. Researchers also plan to enroll an FGR cohort based on the observed PI reduction.

“We believe that the statistically significant reductions in blood pressure and pulsatility index represent on-target responses consistent with DM199’s mechanism of action signaling the potential of DM199 to greatly benefit this underserved patient population,” said Rick Pauls, president and CEO of DiaMedica Therapeutics.

Broader implications for infant health

Managing preeclampsia is vital to reduce not only maternal risks, but also risks in preterm infants such as adverse neurodevelopmental outcomes.² A study published on April 29, 2025, found a negative correlation between hypertensive disorders of pregnancy (HDPs) and Bayley Scales of Infant and Toddler Development (BSID) scores.

In women with HDPs, BSID cognitive and language scores had β estimates of -3.69 and -4.07, respectively. This highlighted increased risks of adverse neurodevelopmental outcomes in preterm infants born to women with HDPs.

References

1. DiaMedica therapeutics reports positive interim phase 2 preeclampsia results: Statistically significant reductions in blood pressure and no placental transfer. DiaMedica Therapeutics Inc. July 17, 2025. Accessed July 17, 2025. https://www.businesswire.com/news/home/20250717976890/en/DiaMedica-Therapeutics-Reports-Positive-Interim-Phase-2-Preeclampsia-Results-Statistically-Significant-Reductions-in-Blood-Pressure-and-No-Placental-Transfer.
2. Krewson C. Maternal hypertension linked to neurodevelopment risks in preterm infants. Contemporary OB/GYN. May 6, 2025. Accessed July 17, 2025. https://www.contemporaryobgyn.net/view/maternal-hypertension-linked-to-neurodevelopment-risks-in-preterm-infants.