Christopher Durang (Photo: John Augustine)

Over his career, Tony Award winner and Pulitzer finalist Christopher Durang has been invited to countless productions of his works. The playwright, whose achievements include a 2013 Best Play Tony Award for his comedy “Vanya and Sonia and Masha and Spike,” frequently attended productions of his plays. But as of late, the usual flurry of invitations have been rejected; until now, no one knew why.

Durang’s family and close friends have shared exclusively with Broadway News that Durang suffers from logopenic primary progressive aphasia (PPA), a disorder of language, which has curbed the prolific author’s career. Because of the rarity of this illness, Durang and his family have struggled with how to convey his condition and limitations, but they want Durang’s fans and the public at large to better understand his circumstances and the disease itself. (Actor Bruce Willis recently announced stepping away from his work due to an aphasia diagnosis, though the variant was not specified.)

Small signs of Durang’s illness first surfaced in 2012, according to Durang’s husband and partner of 36 years, John Augustine. Durang was first officially diagnosed with the condition in 2016 by a neurologist. Later that year, Durang and Augustine sought a second opinion and treatment from Dr. Murray Grossman, who specializes in research tied to this disease, having published his first paper on PPA in 1995. “He was complaining about word-finding difficulty,” said Grossman of Durang at his initial visit. “For somebody who writes plays, that’s a big deal and it’s something that’s easy to notice.”

Grossman, a professor of neurology at the University of Pennsylvania and founding director of the Penn Frontotemporal Degeneration Center at UPenn’s Perelman School of Medicine, confirmed the diagnosis of logopenic primary progressive aphasia, explaining, “‘Aphasia’ is a disorder of language, ‘progressive’ means something that gets worse over time and ‘primary’ refers to the fact that there’s nothing else that can explain what could be causing the problem.” As for the “logopenic” type of PPA, Grossman says, “logo: words; penic: few.”

Logopenic PPA is a rare form of Alzheimer’s disease that is “non-amnestic,” meaning non-memory. So it’s caused by Alzheimer’s but, according to Grossman, “instead of starting in the memory parts of the brain, it’s starting in the language parts of the brain.”

Durang’s long-term memory, in particular, has remained intact. His illness manifests as a difficulty in producing and comprehending speech. He knows what he wants to say; he just can’t access the words. He also struggles to follow lengthy sentences because he can’t hold phrases in his short-term memory to put them together. Augustine compares the condition to being a toddler, where one has few words. Or, imagine you speak Spanish but not fluently. “If people come up to you and start talking quickly in Spanish and want you to answer or explain something technical to them, you know what that feeling is,” says Augustine. “You’re not out to lunch. You know what you want to say; you just don’t know the words. If people interrupt you or try to answer for you, that throws you off.”

Durang is otherwise in good physical health. His movement and motor function are unaffected, as are his visual-spatial skills and executive functioning (like decision-making or impulse control), typical of logopenic PPA. Each of the three variants of PPA (logopenic, semantic and nonfluent-agrammatic) has a different biological cause, which not only results in different symptoms but also requires different treatment.

As the illness’ name indicates, Durang’s condition has worsened with time. He retired from his position at Juilliard in spring 2016, having taught and served as co-chair of the playwriting program since its inception in 1994. He continued to write, albeit slowly, in 2016 and 2017, penning the play “Turning Off the Morning News” (which premiered at the McCarter Theatre Center in 2018) and finishing the book to his friend Wendy Wasserstein’s “Pamela’s First Musical” (which played Two River Theater in 2018). Durang’s final play, “Harriet and Other Horrible People,” has never been produced, though a Nashville theater presented a reading and Durang traveled to see it — the last trip he took alone. After a performance of “Morning News,” Durang participated in one of his last talkbacks, aided in the moment by the McCarter’s then-artistic director Emily Mann.

Only recently has Durang’s disease begun to affect his memory, though it’s mostly been his short-term memory.

“This illness is a terrible illness,” says André Bishop, producing artistic director of Lincoln Center Theater (which produced Durang’s “Sex and Longing” and “Vanya and Sonia”) and a longtime friend of the playwright. “For a writer, in particular, who deals in words, to not be able to find those words is a great sadness.”

The playwright has written more than a dozen full-length plays and more than two dozen one-acts, from the well-known “Marriage of Bette and Boo” to “An Actor’s Nightmare.” He was nominated for a Tony for Best Book of a Musical in 1978 for “A History of the American Film” — about Hollywood’s Golden Age — and named a Pulitzer finalist in 2006 for “Miss Witherspoon” — about a woman who wishes to die but is continually reincarnated on Earth. “Only Chris could do something on this subject and make you roll on the ground laughing,” says Mann.

Durang formally began studying playwriting during undergrad at Harvard and later earned his MFA at Yale, which mounted his first professional production, “The Idiots Karamazov.” Yale is also where he met his lifelong friend and collaborator Sigourney Weaver, with whom he wrote and co-starred in the satiric cabaret “Das Lusitania Songspiel” and who went on to star in many of his plays. “He was a great champion of mine,” says Weaver. “[At Yale] they never cast me in anything…and once I started doing Durang, I think the faculty [noticed]. It sort of put me on the map.” Weaver later repaid the favor. When hosting “Saturday Night Live” for the first time, she brought her pal along.

Durang has had a full career as a writer and actor — from penning titles like “Sister Mary Ignatious Explains It All for You” to “Beyond Therapy,” from performing in the original cast of off-Broadway’s “Putting It Together” to his own “Vanya and Sonia” regionally, and writing screenplays like “House of Husbands” and “The Nun Who Shot Liberty Valance.”

Durang’s diagnosis likely marks the loss of future work from one of the theater’s most original playwrights — so original that Weaver uses his last name as a genre label as in “my love of Durang” and “I still consider Durang my absolute.”

Bishop, who produced Durang’s first off-Broadway play (“Sister Mary”) at Playwrights Horizons and named him one of the theater’s resident playwrights, observes, “The combination that he does so well of kind of crazy, mad, outrageous humor with political points or serious points underneath is just irresistible and [that] exists in almost all his plays. His brand of extraordinarily provocative, over-the-top, absurd humor is what separates him from a lot of writers who are very funny. He’s sort of beyond funny.”

“I don’t know anyone else who writes like him,” adds Mann, who actually first encountered Durang in their undergraduate playwriting seminar at Harvard. “Professor [William] Alfred said, ‘You will be hearing from Christopher Durang,’” Mann recalls. “Of course I followed his every footstep, like a stalker, from then on.” (Indeed, during her 30-year tenure at the McCarter, she produced multiple works of Durang’s — his opening-night present for one production being the offer of a commission for the next.)

But what makes a Durang play irresistible to so many is his balance of absurdity in anguish and humor. “What I love about Durang is that his characters are in genuine pain and they’re in unbearable situations trying to bear up and hope for the best,” says Weaver. “Between [Eugène] Ionesco and [Tennessee] Williams, I feel, is where I find Chris.”

His comedy is considered instinctive, his tone oddball, his characters balancing tenderness, innocence and rage — which, according to his comrades, matches the man who wrote them. Augustine, Bishop, Mann and Weaver all describe Durang as sweet and gentle (“like a little British child,” dotes Augustine), hilarious and silly (“We would just scream with laughter together,” says Weaver) and deeply political (“He cared deeply about the world,” Augustine adds).

According to Augustine, Durang has only gotten sweeter. He still does his best to stay engaged, though political concepts and current events take much longer to explain than they used to.

Humor still dominates. “There’s still a curiosity,” says Augustine. “Unlike somebody far into Alzheimer’s, I think, he’s still curious. So if I laugh at something on TV, he’ll wanna know what made me laugh.”

Currently there is no cure for any form of PPA. Durang participated in a clinical trial using transcranial direct current stimulation, a treatment that administers small electrical currents to the affected centers of the brain while the patient is awake and speaking to measure language proficiency. For Durang, the trial appeared to make minimal if any difference.

Research continues; Grossman and his colleagues at the Penn FTD Center are about to start a medication trial for the semantic variant of PPA. Some medications can help with PPA symptoms and, as Grossman says, “there’re a couple of antibodies that are in the pipeline that are likely — in the near future — to have positive results and then we can start writing a prescription for people like Chris with logopenic PPA.” (There is no known national foundation tied to PPA; for those interested in supporting the cause, the FTD Center welcomes philanthropic support for its research.)

But when it comes to Durang and his work, audiences will have to cherish the dozens of plays he’s already written rather than wait for more. Still, the timelessness of his work, his exploration of human suffering in a chaotic world and his ability to make audiences laugh at that makes Durang ripe for the moment. “I really feel like Durang speaks so much to our today and to our feelings of being overwhelmed in this world that moves so fast and is filled with so many terrifying things,” says Weaver. “More and more, I feel that he speaks to us right now.”