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CHAP trial earns award

David Haas, MD, MS, the Robert A. Munsick Professor of Obstetrics and Gynecology, stands at a podium while speaking to a crowd during Research Day 2023.

David Haas, MD, MS, the Robert A. Munsick Professor of Obstetrics and Gynecology, stands at a podium while speaking to a crowd during Research Day 2023.

A study co-authored by an Indiana University School of Medicine faculty member, which showed treating even mild preexisting high blood pressure during pregnancy improves maternal and fetal outcomes, has been named Clinical Trial of the Year by the Society of Clinical Trials (SCT).

The Chronic Hypertension and Pregnancy (CHAP) trial was given the David Sackett Trial of the Year award by SCT, a celebrated international organization of professional researchers. The award is given annually to the leaders of one randomized, controlled study that has provided a substantial change to the healthcare field.

The results from the CHAP trial consortium come from more than 60 clinical sites across the United States, led by Alan Tita, MD, PhD, the Senior Vice Chair for Research and Innovation, Department of Obstetrics and Gynecology, Center for Women’s Reproductive Health, Marnix E. Heersink School of Medicine, University of Alabama at Birmingham.

David M. Haas, MD, MS, the Robert A. Munsick Professor of Obstetrics and Gynecology, led the work of the collaborators at Indiana University.

More than 2 percent of pregnant women in the United States have chronic hypertension, or high blood pressure. While medical professionals agreed that severe chronic hypertension during pregnancy should be treated with medications, they were divided for decades over whether to treat non-severe or mild forms of chronic hypertension during pregnancy.

Results from the CHAP trial – which were published in the New England Journal of Medicine in April 2022 – showed that treating mild chronic hypertension with medications is safe. The findings provided for the first time comprehensive, evidence-based data for treating non-severe forms of chronic hypertension during pregnancy.

The work garnered the CHAP trial a nomination for the David Sackett Trial of the Year.

Nominations are submitted by SCT members, investigators and interested scholars from around the world, and the award is presented to the trial that fulfills the following standards:

- Improves the lot of humankind.
- Provides the basis for a substantial, beneficial change in health care.
- Reflects expertise in subject matter, excellence in methodology, and concern for study participants.
- Overcame obstacles in implementation.
- The presentation of its design, execution, and results is a model of clarity and intellectual soundness.
- Consistent with the overall aims of the Society, we support the goals of equity, diversity, and inclusion. We welcome all nominations regardless of trial setting, investigator, or patient group.

The CHAP consortium launched in 2014 with funding from the National Institutes of Health’s Heart, Lung and Blood Institute. From September 2015 to March 2021, CHAP enrolled more than 2,400 pregnant women with known mild chronic hypertension, whose blood pressure was greater than 140/90 mmHg but less than 160/105 mmHg.

Notably, the CHAP trial is one of the most comprehensive and diverse studies of its kind. The Black patient population is disproportionately affected by chronic hypertension, and almost 50 percent of study participants were Black.

Participants were randomized into active and standard treatment groups. The active group was prescribed blood pressure medication, mostly labetalol or nifedipine, to keep blood pressure below 140/90 mmHg. The standard group received medication only if a participant developed more severe hypertension, or a blood pressure greater than 160/105 mmHg. Participants were evaluated in routine clinic visits through six weeks after delivery.

There was an almost 20 percent decrease in pregnancy complications for women treated with medication compared to the standard group: Severe preeclampsia was reduced from 29 to 23 percent; and preterm births before 35 weeks’ gestation were significantly reduced, from more than 16 to 12 percent.

Haas’ research at IU is mostly focused on obstetrics, encompassing many areas, with particular interest in medications in pregnancy and biobanks. All of these are focused on improving obstetric and newborn outcomes. He is the Vice-Chair for Research for the Department of Obstetrics & Gynecology and the Medical Director for Statewide Research for the Indiana Clinical and Translational Sciences Institute.

Read the full press release, here