Trish Vradenburg, wearing her mother's pearl necklace, in 2013. (Joshua Yospyn/for The Washington Post)

Trish Vradenburg, a television screenwriter and humorist who became a nationally known activist for Alzheimer’s research after losing her mother to the disease, an experience she chronicled with biting humor in a play, “Surviving Grace,” died April 17 at her home in Washington. She was 70.

The cause was a heart attack, said her husband, George Vradenburg, a former general counsel and senior executive for CBS, Fox and AOL Time Warner. Ms. Vradenburg served at the time of her death as vice chairman, with George Vradenburg serving as chairman, of UsAgainstAlzheimer’s, an advocacy group the couple founded in 2010 with the stated goal of “ending Alzheimer’s by 2020.”

By the late 1980s, Ms. Vradenburg once recalled, her “professional life was finally on track.” She had screenwriting credits on “Kate & Allie,” “Designing Women” and “Family Ties,” had written magazine and newspaper humor columns and had published a romance novel, “Liberated Lady” (1986). But for her mother, Bea Lerner, “life suddenly began to unravel.”

“The phone calls started. I started hearing from Mother, and I didn’t like what I was hearing,” she recalled in a 2013 interview with The Washington Post. “My mother was a lioness, a powerhouse. . . . But that’s not who was calling me. I could hear her retreating, spiraling down. It just got worse. The confusion, the paranoia. The phone would ring, and I’d brace myself. My mother was no longer my mom.”

Lerner died in 1992. Ms. Vradenburg marshaled her grief — as well as her sense of humor — to write a play first titled “The Apple Doesn’t Fall …,” about a TV screenwriter whose lovably if annoyingly overbearing mother fades away with Alzheimer’s. The play turns on a miracle drug that grants her — and her daughter — temporary relief from the illness.

Trish Vradenburg and her husband, George, in 2011. (Rebecca D'Angelo/For The Washington Post)

“I felt totally guilty that I was working and wasn’t paying the attention I should,” Ms. Vradenburg told The Post. “My mother disappeared into the chasm of Alzheimer’s so remarkably quickly . . . It’s not really about Alzheimer’s as much as it is about a mother and daughter reconnecting and understanding and letting go.”

The play opened in 1996 at New York’s Lyceum Theater, directed by Leonard Nimoy and starring Margaret Whitton and Florence Stanley. Amid unfavorable reviews, it closed after one performance.

Remarking to the New York Times that “nothing worth attaining is won by fleeing,” Ms. Vradenburg reworked the play and introduced it again in 2001 at the Kennedy Center’s Terrace Theater (directed by Jack Hofsiss and starring Ilana Levine and Doris Belack) — and the next year at New York’s Union Square Theater (starring Illeana Douglas and Belack). The Vradenburgs provided funding for advertising.

Ms. Vradenburg quipped that “I could have gotten better reviews had I been a member of the Taliban,” but audiences turned out in large numbers for performances. She said she saw the play as a “cause,” helping to reduce the stigma of a disease that affects the lives of as many as 5 million American patients and millions more family members and caregivers. Comedian Carol Burnett portrayed the mother in a 2013 performance to benefit Alzheimer’s research.

Patricia Ann Lerner — she later changed her middle name to Lois — was born in Newark on May 9, 1946. Her father was a judge and later chief of New Jersey’s Division of Alcoholic Beverage Control. Her mother was a philanthropist and Democratic Party activist.

Trish, as Ms. Vradenburg always was known, received a bachelor’s degree in political science from Boston University in 1968 and married her husband the same year. Besides George Vradenburg of Washington, survivors include two children, Alissa Vradenburg of West Hollywood, Calif., and Tyler Vradenburg of Chicago; a brother and four grandchildren.

Early in her career, Ms. Vradenburg worked as a speechwriter for U.S. Sen. Harrison A. Williams Jr. (D-N.J.). The Vradenburgs were active donors to both political parties — she was a Democrat, he a Republican — but together they promoted what they dubbed the Alzheimer’s Party, a bipartisan group that supported increased funding to fight the disease.

Ms. Vradenburg served on the council of Theater J in Washington and on the board of the Vradenburg Foundation. Washingtonian magazine named the couple Washingtonians of the year for 2016.

“We have to start talking about Alzheimer’s,” Ms. Vradenburg told The Post in 2013. “We have to get people to come out of the closet and demand research, money, a cure, a vaccination, anything! We need more money, and I’m not going to stop asking for it. I’ve got nothing to lose now. I will shake a congressman. I recently told one that if he had any questions, I’d be waiting right outside his door. You don’t have a mother like mine and not stick around for as long as it takes.”