WASHINGTON -- Shortly before noon on May 26, 2015, the Russian political activist Vladimir Kara-Murza, Jr., left his apartment in central Moscow for a typical workday: huddling with colleagues to discuss challenging President Vladimir Putin's authoritarian rule. He took the tram to a nearby restaurant, where he met a fellow member of RPR-Parnas, the liberal opposition party founded by slain Putin critic Boris Nemtsov. He ate a buffet-style lunch, washed down with a glass of cranberry juice. He appeared "energetic and happy," his dining partner recalled two days later.
The activists parted ways at around 1 p.m. near the central Park Kultury metro station, where Kara-Murza met fellow political operative Mikhail Yastrubitsky. The two men took a short walk to the massive Soviet-era office complex that houses state media behemoth Rossiya Segodnya for a meeting with a former colleague. The get-together remained uneventful -- and Kara-Murza's mood buoyant -- for about two hours, during which time the three men had nothing to eat or drink. Suddenly, Kara-Murza began sweating profusely, his heart racing and his body hit by waves of nausea.
"Within the space of maybe 10 to 15 minutes I went from feeling normal to feeling really sick," he told RFE/RL in a recent interview at a cafe in Washington's Georgetown district.
Kara-Murza rested his head on the table in the conference room, using his arms as a pillow, and appeared to be losing consciousness, Yastrubitsky recalls. "I went to take him out into the hallway to put him on a small couch there. We didn't even make it to the couch. He began vomiting," he said.
Yastrubitsky hitched the rapidly weakening Kara-Murza to his shoulder and dragged him to the bathroom to wash up, but the vomiting persisted. Kara-Murza asked Yastrubitsky to call an ambulance, which arrived around 30 minutes later. "He was limp and was speaking very slowly. He basically couldn't move his legs or arms. He would close his eyes periodically, and we kept talking to him to keep him conscious," Yastrubitsky told RFE/RL.
"I thought it was just food poisoning," he added. "It happens."
The ambulance shuttled Kara-Murza to City Hospital No. 23, where doctors diagnosed him with a cardiac defect. Shortly before midnight, they transferred him to one of Russia's leading heart clinics, where doctors considered operating on his heart, according to medical documents seen by RFE/RL and interviews with those who were with Kara-Murza at the time. But when his family and friends arrived the next morning, a surgeon greeted them and said the surgery had been canceled, according to Kara-Murza's lawyer, Vadim Prokhorov.
"He said there's no heart problem here, that it's some kind of severe poisoning," Prokhorov told RFE/RL.
The diagnosis immediately triggered fears of foul play among Kara-Murza's friends, family, and supporters both in Russia and in Washington. At age 33, he was already a veteran of opposition politics. The son of a prominent Russian journalist, also named Vladimir, who hosts a talk show on RFE/RL's Russian Service, Kara-Murza mounted an unsuccessful bid for a seat in parliament in 2003 with the backing of the country's two leading liberal parties. He also served as a key liaison between the Russian opposition and officials in the U.S. capital, where he had worked as journalist for nearly a decade before joining projects backed by former oil tycoon Mikhail Khodorkovsky, a Putin adversary who is now trying to mobilize political opposition forces from exile in Europe.
Three months before Kara-Murza fell ill, Nemtsov, a former Russian deputy prime minister who became one of Putin's most prominent opponents, was shot dead 100 meters from the Kremlin. Kara-Murza and Nemtsov had been close friends and allies. Nemtsov was the godfather to his younger daughter. And both men had lobbied vigorously in Washington for the Magnitsky Act, a U.S. law imposing sanctions on Russians deemed complicit in human rights abuses that infuriated the Kremlin after it was signed by President Barack Obama in December 2012. Kara-Murza had also served as a coordinator with Khodorkovsky's nongovernmental organization, Open Russia, since its relaunch in September 2014, crisscrossing the country to meet with opposition activists and conduct seminars.
With heart surgery off the agenda, Kara-Murza was transferred from the cardiac center to the intensive care unit at the nearby Pirogov clinic, a top medical facility in Moscow, where his condition worsened. Over the next 72 hours, his brain swelled and his major organs -- lungs, heart, kidneys, liver, intestines -- proceeded to fail.
Yastrubitsky recalls his doctors saying: "We see from all the symptoms that this is a poisoning, but we don't understand the nature of this poisoning. … And we don't know where the source of the poisoning is."
Suspecting The Worst
Several Kremlin antagonists, both at home and abroad, have died or become violently ill in suspected deliberate poisonings during Putin's 16 years in power. Most famously, former Federal Security Service (FSB) officer Aleksandr Litvinenko died in November 2006 after ingesting the rare radioactive isotope polonium-210 in London. British authorities accuse fellow ex-FSB officer and current Russian lawmaker Andrei Lugovoi of delivering the poison over tea at a London hotel, an allegation Lugovoi denies. Ukraine's former pro-Western president, Viktor Yushchenko, was left with a disfigured face due to dioxin poisoning during his 2004 presidential campaign against Kremlin ally Viktor Yanukovych. Yushchenko implied his poisoning was a state-sponsored attack and accused Russia of impeding efforts to investigate it.
That same year, Russian investigative journalist Anna Politkovskaya was severely sickened after drinking a cup of tea on an Aeroflot flight from Moscow to southern Russia during the Beslan school-hostage crisis. Her editor at the independent newspaper Novaya Gazeta, Dmitry Muratov, said at the time that he believed Russian authorities poisoned Politkovskaya but were trying to "incapacitate" her, not kill her. Two years later, she was shot dead in her apartment building in Moscow.
Former FSB officer Aleksandr Litvinenko died of polonium poisoning in 2006.
Another Novaya Gazeta journalist, prominent anticorruption crusader and liberal parliamentarian Yury Shchekochikhin, died in July 2003 following a painful, weeks-long battle with a mysterious illness that his colleagues are convinced was a deliberate poisoning. Muratov and fellow Novaya Gazeta editor Sergei Sokolov have long accused authorities of stymieing the investigation into Shchekochikhin's death.
When Kara-Murza's doctors returned with the poisoning diagnosis, "of course we suspected the worst," Prokhorov told RFE/RL. "Three months earlier Nemtsov was murdered, and Shchekochikhin 12 years before that," he said.
After Kara-Murza was first taken to the hospital, Yastrubitsky phoned Kara-Murza's wife, Yevgenia, in Centreville, Virginia, a Washington suburb where she lives with the couple's three children. She was frightened and perplexed to learn that her husband, who splits his time between Centreville and Moscow, was diagnosed with a faulty heart. "But it was something I could digest, at least," she told RFE/RL.
Yevgenia says she was making childcare arrangements and preparing to fly to Moscow for the surgery when she was informed that the diagnosis had been changed to acute poisoning "of an unknown origin."
"It was a much worse prognosis," she recalled. "It's something you can't wrap your head around."
Diplomatic Pressure
With Kara-Murza in critical condition, Yevgenia began frantically seeking help from influential friends, colleagues, and supporters of her husband. She spoke to Khodorkovsky, who would ultimately pay Kara-Murza's medical bills, as well as Bill Browder, the U.S.-born British financier who was the driving force behind the Magnitsky Act. In 2012, Browder and Kara-Murza testified together in the Canadian parliament, urging lawmakers to adopt similar legislation imposing sanctions on alleged Russian rights abusers.
WATCH: Vladimir Kara-Murza, Jr. In The Canadian Parliament
"It was clear to me that if this was an act of deliberate poisoning, then the Russian authorities weren't going to do much to help him," Browder told RFE/RL.
Kara-Murza's contacts in the U.S. Congress, where he had testified about human rights in Russia under Putin, began raising his plight among State Department officials and the American media in the hopes that publicity and diplomatic pressure could help facilitate his medical evacuation from Russia and independent toxicology testing abroad.
"Since the doctors cannot come up with a definite source of his intoxication, we do not know how safe he is there," Yevgenia told The New York Times a day after her husband fell ill. "That's why we are trying to attract as much attention to his condition as we can."
Yevgenia appealed to U.S. State Department officials for help, though Kara-Murza would not be entitled to formal consular assistance from the U.S. Embassy in Moscow: She and her husband hold U.S. green cards but, unlike their children, are not American citizens. As a teenager, however, Kara-Murza went to live with his mother in Britain, where he graduated from Cambridge University and acquired British citizenship before returning to Russia in 2003. This raised the prospects of securing support from British diplomats in the Russian capital.
Browder, who is based in London, reached out to the British Foreign Office, which in the days after Kara-Murza was hospitalized publicly confirmed it was "providing consular assistance to a dual British national taken ill in Moscow."
Behind the scenes, the Foreign Office informed the Russian government of its interest in Kara-Murza's case and authorized the British Embassy in Moscow to provide consular support on an exceptional basis in light of the fact that he was a Russian citizen on Russian territory, according to a document seen by RFE/RL.
U.S. diplomats in Moscow coordinated on the matter with the British Embassy, which took the lead given Kara-Murza's dual citizenship. In Washington, meanwhile, the State Department remained tight-lipped about its involvement, saying it was "following developments closely" and that Kara-Murza "is in our thoughts and we expect he'll receive the best medical care possible."
Word of his case reverberated among the upper echelons of the Obama administration. Deputy Secretary of State Antony Blinken monitored developments in Kara-Murza's illness. Also briefed on the matter were Assistant Secretary of State for European and Eurasian Affairs Victoria Nuland and Celeste Wallander, senior director for Russia and Central Asia on Obama's National Security Council, RFE/RL has learned. Senior members of Congress, meanwhile, voiced alarm for the ailing political activist's well-being.
"I am deeply concerned about the mysterious illness of Vladimir Kara-Murza, especially given the recent murder of Boris Nemtsov and the number of Putin's opponents who have been poisoned," U.S. Representative Chris Smith (Republican-New Jersey), the chairman of the U.S. Helsinki Commission, said in a May 28 statement. "I strongly urge the Russian government to guarantee Mr. Kara-Murza's safety and facilitate his transfer to a hospital outside of the Russian Federation for further evaluation and care."
The same day, Yevgenia Kara-Murza sent an email to RFE/RL and other media outlets saying the hemodialysis that her husband was undergoing "has not had any effect." She urged his evacuation "to a medical center in Europe or Israel where full toxicology testing and treatment can be done."
The British Foreign Office told RFE/RL at the time that it does not offer medical evacuation as part of its consular services and advised "people to follow the advice of medical professionals."
By the time Yevgenia arrived in Moscow on May 29, the question of evacuation was already obsolete. Kara-Murza's Russian doctors and an Israeli specialist hired by Khodorkovsky to monitor his care estimated that he had about a 5 percent chance of survival, and that moving him was simply too dangerous.
Antidepressant Enigma
On the day of her arrival, Yevgenia says, her husband's doctors informed her of a preliminary diagnosis: poisoning by citalopram, a widely prescribed antidepressant that Kara-Murza had been taking for several years. The diagnosis was first picked up in the media by the sensationalistic pro-Kremlin website LifeNews, setting the tone for the narrative about the cause of his illness that would prevail in the Russian press in the ensuing weeks: that Kara-Murza poisoned himself with antidepressants, most likely accidentally.
The theory struck Yevgenia as strange. She says her husband had never experienced any problems with citalopram, which belongs to a class of drugs known as selective serotonin re-uptake inhibitors (SSRI) and is considered very safe. He never exceeded his prescribed dosage, she adds.
Kara-Murza's doctors, Yevgenia says, suggested that he may have suffered from an undiagnosed kidney problem that could have allowed the drug to build up to a dangerous level in his system.
Vladimir Kara-Murza and his wife Yevgeniya
Yevgenia says the doctors also posited that the citalopram may have had a dangerous interaction with his allergy medicine, the nasal spray Flonase. However, several toxicologists told RFE/RL that the active ingredient in Flonase, fluticasone propionate, does not interact with citalopram. Nor does ranitidine hydrochloride, the active ingredient in Zantac, a common antacid he was taking, the toxicologists said.
Eran Segal, an Israeli doctor brought in by Khodorkovsky to monitor Kara-Murza shortly after his hospitalization, also cast doubt on the theory that citalopram had something to do with his illness.
"It is not the usual picture, whether an overdose is deliberate or inadvertent," Segal told the BBC in June. "It could be a severe infection or maybe some other toxin we are not aware of. But there is no evidence of the cause," Segal added.
Yevgenia pressed the doctors for a more exhaustive analysis of the potential source of her husband's poisoning but said that "basically they kept saying that the cause didn't matter for the treatment, that the treatment would have been the same in any case of intoxication."
She made a snap decision and demanded that the doctors take blood, urine, hair, and nail samples for an independent toxicological analysis. She says, however, that "for some reason the Russian doctors were very much against it" but "didn't say why."
"They started talking about his nasal spray. That sounded ridiculous to me, and I requested samples for analysis. Basically I said: 'Well, if you don't want to do it here, I want to do it elsewhere, because I'm not satisfied with your answer,'" Yevgenia says. "With some difficulty, but we managed to get the samples."
Matters Of Substance
Aleksei Svet, the chief doctor at the Pirogov clinic, rejected accusations that his medical team did not try hard enough to determine the cause of Kara-Murza's illness. "If that's what they say, let that be on their conscience," he told RFE/RL. "Because during treatment, all the toxicology was taken."
With the samples in hand, the search began for a laboratory -- in Russia or abroad -- that could provide a thorough and independent toxicological assessment.
British financier Bill Browder
Browder told RFE/RL that he contacted the Foreign Office, which he says initially agreed to help transport the samples to Britain. He suggested using diplomatic pouches to get the samples out of the country, with the plan to have them analyzed at the same laboratory that tested Litvinenko's blood.
The Foreign Office, however, said this would not be possible, citing the Vienna Convention on Diplomatic Relations, which states that such packages "may contain only diplomatic documents or articles intended for official use."
Ultimately, Browder says, British diplomats provided the contact information for international couriers DHL and FedEx in Moscow.
A Foreign Office spokesman told RFE/RL this week that "unfortunately" the Vienna Convention prevented it from meeting "a request for retrieval and transfer of items in the diplomatic bag."
The spokesman added it that it had "a dedicated team working on the case in London and at the British Embassy in Moscow" at the time.
"Embassy staff attended the hospital where Mr. Kara-Murza had been admitted and were in contact with his family," the spokesman said. "We provided support, including offering details of medical assistance companies."
Within hours after collecting the samples, Yevgenia says, they found someone who agreed to take them to France on short notice to be analyzed at the laboratory of Pascal Kintz. A renowned forensic and analytical toxicology expert based in the town of Oberhausbergen, Kintz had previously analyzed samples from Shchekochikhin's exhumed corpse that were smuggled out of Russia by his editors at Novaya Gazeta.
Kintz's analysis of Kara-Murza's blood, hair, urine, and nail samples did not offer any firm conclusion about what may have poisoned the activist. He found a normal level of citalopram in Kara-Murza's blood if the patient's last exposure to the drug occurred on the same day his blood was collected. But because the blood sample was taken three days after Kara-Murza became sick -- and assuming that he did not ingest citalopram after his symptoms began -- Kintz calculated that the drug's blood concentration may have greatly exceeded the recommended dosage on the day he fell ill.
In a healthy individual, this could indicate the ingestion of a toxic amount of the drug. But citalopram is eliminated by the liver and the kidneys, both of which failed in Kara-Murza after his hospitalization. Kintz noted in his report, dated June 15 and seen by RFE/RL, that his calculation "is only valid in case there is no defect in metabolism (liver failure) or elimination (kidney failure)."
Bruce Goldberger, chief of the Toxicology Division for the Department of Pathology, Immunology and Laboratory Medicine at the University of Florida's College of Medicine, concurred.
"If [Kara-Murza] was in liver failure and kidney failure, [Kintz's] calculation would be off," Goldberger told RFE/RL. "In the case of organ failure, his body would have a difficult time eliminating the drug, which could, a few days later, give an elevation of the blood-drug concentration. So you have to be really cautious."
Michael Whitekus, a Pennsylvania-based toxicologist and drug-safety expert, said Kara-Murza's "kidney dysfunction probably contributed to" an increased level of the citalopram in his blood.
"Everything you're seeing is probably secondary to what the primary toxin was," Whitekus said.
If Kara-Murza had ingested an excessive amount of citalopram, the symptoms would have presented themselves within 30 minutes or an hour, Goldberger added. But Kara-Murza says he never exceeded his prescribed dosage and did not take his medicine with him when he left his apartment that morning. Furthermore, he had been in a meeting for two hours when he suddenly fell ill.
Goldberger and Whitekus echoed the assessment by Segal, the Israeli doctor who observed Kara-Murza in Moscow, that his symptoms did not appear consistent with citalopram poisoning.
"When you talk about major organ failure, you have to think something more [like] a poison that causes widespread effects on body than what the citalopram would," Goldberger said.
Whitekus added: "It doesn't make sense to me."
Svet, the chief doctor of the Pirogov hospital in Moscow, alluded to Kintz's report in defending his medical team's primary diagnosis of citalopram poisoning. "The results came back: absolutely the same as our findings," he told RFE/RL. "So this question is not for me. I understand, of course, it's frustrating that things didn't turn out so heroically. But maybe it's for the best."
"Believe me, everything is much more prosaic and has nothing to do with a bloody regime," Svet added.
He quoted a line from Lewis Carroll's Alice in Wonderland -- "If you drink much from a bottle marked 'poison,' it is almost certain to disagree with you, sooner or later" -- and that "certain" beverages may have played a role in Kara-Murza's illness.
"Certain medications taken together with certain types of beverages, consumed unchecked, in general became the reason for this story," Svet told RFE/RL. He declined to elaborate, citing doctor-patient confidentiality.
Goldberger, the toxicologist at the University of Florida, said in an e-mail that "acute (recent) alcohol intoxication" plus citalopram ingestion could be responsible for the rapid onset of severe symptoms, including major organ failure. "Citalopram is a very safe drug, even when co-ingested with alcohol -- unless too much of one or both are ingested," he said.
He added: "However, I'm still not convinced that a mix of alcohol and citalopram was responsible for Mr. Kara-Murza's illness. Alcohol alone could be if he ingested too much."
Kara-Murza told RFE/RL that he had not drunk any alcohol the day he was taken ill -- only "water and cranberry juice."
"This is probably stating the obvious, but it was the middle of the day, and I was at a work meeting," he said.
Several medical records related to Kara-Murza's illness -- from both Russian and foreign specialists -- reviewed by RFE/RL make no mention of alcohol in his system. Yevgenia said his doctors "were not even considering alcoholic intoxication" and that none of her husband's medical records indicate the presence of alcohol in his blood.
'Miracle' Recovery
While Kara-Murza's family and friends were frustrated with what they considered his doctors' lackluster efforts to determine the source of his poisoning, they had only praise for the medical treatment he was receiving.
On May 31, a day after Kintz analyzed Kara-Murza's biological samples, Yevgenia arrived at the hospital and was told by Segal, the Israeli doctor, that his condition had improved "like a miracle."
Over the next several days, Kara-Murza was able to open his eyes and recognize his relatives. His condition steadily improved, though he says he does not remember his time in intensive care at all. The last thing he remembers before his coma was being prepped for heart surgery. The first thing he remembers after regaining consciousness is being moved to a neurology department one month after he collapsed.
He remained hospitalized in Moscow until July 5, when a medical evacuation plane paid for by Khodorkovsky flew him to Washington to be closer to his family. He spent three weeks in a hospital outside the U.S. capital, where he says he "basically learned to walk again."
Kara-Murza told RFE/RL that he has nothing but gratitude for his Russian doctors for saving his life, but he dismisses their diagnosis of citalopram poisoning.
"I hadn't taken any new medicines in years," he said, adding that the Russian doctors had ruled out the possibility of food poisoning. "I hadn't changed my routine of my medicines in years."
Nearly eight months after being struck by a near fatal illness, Kara-Murza still suffers from nerve damage on the left side of his body, though he says his doctors expect him to fully recover this year. In the meantime, he walks with the help of a cane, which he clutches in his right hand. His left hand is too weak to grip the handle.
'Deliberate Poisoning'
On December 11, Kara-Murza and Prokhorov, his lawyer, submitted a request to the Investigative Committee, the powerful Russian analogue of the FBI, to investigate his poisoning as attempted murder.
"I have no doubt for a second that this was deliberate poisoning, that this was deliberate poisoning aimed to kill, and that it was motivated by my political activities," said Kara-Murza, whose fluent English is tinged with a British lilt. "I was a healthy 33-year-old man. Suddenly, when all of your major organs shut down within 24 hours, one after another -- that doesn't just happen."
He says he faced no specific threats prior to his illness but that he suspects he may have been targeted due to his work for Open Russia, in order to send "a message" to Khodorkovsky.
Khodorkovsky spent a decade in prison on financial crimes convictions that he and his supporters say were engineered by top officials as retribution for his failure to toe the Kremlin line. He was pardoned by Putin, freed, and immediately flown out of Russia in December 2013, and has become increasingly active in his opposition to the Kremlin since then. The Investigative Committee last month formally charged him in absentia with ordering the 1998 killing of the mayor of the oil town Nefteyugansk.
Vladimir Kara-Murza, Jr. still hasn't recovered fully from his ordeal.
Kara-Murza also believes his poisoning may have been an act of revenge for his lobbying for U.S. sanctions against Russian officials under the Magnitsky Act, named for Sergei Magnitsky, a whistleblowing Russian lawyer who died in a Moscow jail in 2009 after accusing officials of large-scale fraud.
A month before his illness, Kara-Murza and opposition politician Mikhail Kasyanov, Putin's former prime minister, met with U.S. lawmakers in Washington to request that the United States impose Magnitsky Act sanctions on Russian television "propagandists" they accuse of leading a media vilification campaign that helped lead to Nemtsov's slaying.
Whether his illness will ever be definitively established as the result of an attack, an accident, or something else remains unclear. By the time Kintz conducted his analysis of Kara-Murza's biological samples, his blood had already undergone purification with hemodialysis.
The hair samples are more promising, but only to a point.
"If it's in the blood, it's going to be in the hair," said Whitekus, the Pennsylvania-based toxicologist. "The problem is you have to know what to look for. And once you evaluate those hair samples for compound A and you don't find it, you're done, because you've got limited resources. You almost have to know ahead of time what you're looking for. And that's the needle in the haystack.
"Whatever it is, I don't think it's the citalopram," he said.
Back To Russia
Whether the Investigative Committee will ultimately open a formal criminal case in connection with Kara-Murza's poisoning remains unclear. Judging by committee spokesman Vladimir Markin's dismissive comments, it appears unlikely.
Reached by RFE/RL on January 12, Markin chided a reporter for asking "provocative questions" and "worrying" about a single case of poisoning when "sometimes people are poisoned by shoddy food and beverages" imported from the West.
"People are sickened and even die from Scotch whiskey," he said. "Why are you worried about this one specific poisoning of a single person who survived?"
He added: "Who is Kara-Murza, and who are the thousands of people that die daily in the world for various reasons, in England, in America, in Europe? Why are you not worried about the issue of German police not resisting violence against women?"
But on January 15, investigators from a Moscow branch of the Investigative Committee asked to meet with Kara-Murza to discuss his request for a criminal case, his lawyer, Prokhorov, told RFE/RL.
He added, however, that the fact that he was contacted by the agency's local branch in the Russian capital's Khamovniki district indicates that authorities are not taking the request for an investigation seriously.
"The fact that they gave this, in my opinion, very important matter to the lowest level possible...probably shows that they're not terribly interested in it," Prokhorov said.
Kara-Murza said he welcomes the development and plans to meet with investigators when he travels to Moscow next week to "give them all the necessary information."
"However, the fact that it took them more than a month to begin the check, and that the case was transferred to the district level, points to a lack of priority," he said.
He noted that criminal cases against foes of Putin are often handled by more senior investigators. He said this shows that "politically motivated cases against Kremlin opponents are of much greater interest to the Investigative Committee than an attempted murder of an opposition member."
If authorities ultimately declined to launch a formal investigation, Kara-Murza says he still believes that one day evidence will emerge that his poisoning was an attempt on his life. "Maybe one day we’ll find out, when the archives are opened or when somebody talks once the regime changes,” he said.
During his forthcoming trip to Russia, he plans to continue his work for Open Russia, including preparations for September parliamentary elections, a test of Putin's grip and a chance for his embattled opponents to attempt to pose a challenge.
"Probably every single person that I spoke to since my poisoning advised me not to return to Russia and not to resume my work," he said. "But for me this is a question of principle. It is my country, I think we're doing the right thing. And I'm not going to run away. I'm not going to hide."
Yevgenia paused when asked about her husband's plan to continue working in Russia.
"It's hard to say. We have three kids, and he's the man of my life. But on the other hand, he is the person I married many years ago, and he was the same back then," she said. "Nothing has changed in that regard. And we've always known that there were risks, and after Boris [Nemtsov’s] death in February, these risks became more tangible. … But Vlad really believes in what he's doing."