The case against former pharmacist Barry Cadden is now in the hands of a federal jury.

Cadden co-owned and ran the New England Compounding Center, the Framingham pharmacy responsible for a nationwide meningitis outbreak in 2012. Contaminated injections produced by the pharmacy killed at least 64 people and sickened more than 700 people.

Jurors are now deliberating on whether Cadden is guilty of the 96 charges—including fraud, racketeering and 25 counts of second-degree murder.

Here’s what you need to know about the trial and the 2012 outbreak:

1. What exactly happened in 2012?

In September of 2012, people began to notice a mysterious outbreak of fungal meningitis and other infections in multiple states. This mystified physicians because it’s incredibly rare—and incredibly dangerous. Meningitis is when the membrane around the brain and spinal cord is inflamed.

The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA)—along with state and local officials—jumped into action. They ultimately traced the deadly outbreak to Cadden’s compounding pharmacy named the New England Compounding Center.

His outfit had been shipping out steroid injections that were meant to treat pain. However, they were contaminated with mold. The result was the worst outbreak of meningitis in U.S. history.

 An official from the CDC testified during Cadden’s trial that this meningitis outbreak was comparable to the Ebola outbreak in West Africa. However, he said, it was worse because it was entirely preventable.

Ebola was huge news back in 2012, but Cadden’s trial has not generated the same media attention. That’s partly because it was fairly technical, delving into concepts such as air sampling and fungal blooms.

2. What happened at the trial?

This was a long trial (more than nine weeks of testimony) and it’s a complicated one (with nearly 100 charges). However, there are two broad issues in the case:

Cleanliness and testing

Federal prosecutors argued that Cadden’s compounding pharmacy flouted safety standards to the point of being downright filthy. In the so-called “cleanroom” where sterile drugs were made, the prosecutors said there were flies, oozing oil, and mold.

Under Cadden’s direction, prosecutors said, the pharmacy used expired ingredients, fabricated cleaning logs, and improperly tested the drugs. Prosecutors said Cadden knew his injections could harm or kill patients, yet he still shipped them out. They compared it to a game of Russian Roulette and have charged Cadden with 25 counts of second-degree murder.

Cadden’s defense attorneys presented a very different picture. They accept that people died from drugs produced at Cadden’s pharmacy but, they said, this was not a case of murder.

Defense attorneys argued that Cadden always sought to go above and beyond best practices for the industry, particularly when it came to cleaning. He used an outside lab for testing and, over the years, his pharmacy sent out hundreds of thousands of medications without incident. They say prosecutors cherry-picked the worst lab results, creating a deceptive picture.

But of course, some of the drugs were contaminated with mold. For that, Cadden’s lawyers blame contractors and employees at the pharmacy. In particular, they point to Cadden's business partner, Glenn Chin, who was the supervisory pharmacist and will soon face his own trial.

Avoiding regulatory oversight

Federal prosecution argued that Cadden went to great lengths to lie to customers and skirt regulations. They showed the jury a training video in which Cadden dismissed the idea that inspectors would catch up with him.

“How can they come in and inspect me?” he asked in the video. “They have no clue what they are looking at. They go around and they’re like: ‘Barry’s place looks great. Yah, I got to go [get a] cup of coffee.’ Really. That is what it is like.”

Prosecutors detailed a complex scheme involving fabricated prescriptions. In an email, Cadden told his employees to make sure bogus patient names did not seem too fake—"No names like Mickey Mouse," he wrote.

In the training video, an employee asked Cadden about patient names and Cadden responded, “That’s actually one of the more difficult things we do. Let’s just talk about the product now, while we are being recorded.”

By appearing to sell custom-made medications for individual patients, Cadden's outfit fell under state regulation as a retail pharmacy. The goal, prosecutors said, was to hide what was really going on: bulk sales that would have subjected Cadden’s pharmacy to federal oversight as a drug manufacturer.

Cadden’s defense attorneys said it was Cadden’s employees and customers who fabricated the prescriptions—not Cadden himself. And, they said, as soon as Cadden knew about problems he acted aggressively and appropriately to fix them. Plus, they pointed to a regulatory landscape that was incredibly murky and showed that lots of compounding pharmacies were struggling to figure out the regulations.

3. Why is Cadden charged with second-degree murder?

Murder is usually decided on the state level, not on the federal level. In this case, the prosecutors listed the second-degree murder counts under their racketeering charges. Federal prosecutors argued that they didn’t need to prove intent to murder. Instead, they said proving Cadden acted with “extreme indifference to human life” was enough.

However, Cadden’s defense attorneys want the government to prove intent. During their closing arguments, they told jurors that at the very beginning of the 2012 meningitis outbreak, Cadden spent the night as his pharmacy. He called clinics who had received his drugs and left voicemails warning them to be careful.

In one message he said, “We would like you to quarantine this product at this point and call us as soon as possible to discuss the situation. Again, Barry at New England Compounding. We consider this an emergency.”

“Are those the words of a murderer?” asked Cadden’s defense attorneys. They argue that Cadden never intended to kill people, and that prosecutors failed to show exactly what Cadden did to cause the deaths.

4. Separate from Cadden’s trial, what’s been the long-term impact of the outbreak?

First, the victims.

Many of the victims who survived the outbreak still have health problems.

Kristen Townsley of Alabama is one of them. She has juvenile rheumatoid arthritis and, at the time of the outbreak, she was on a carefully calibrated drug regimen. After receiving three of the contaminated injections, she says, she was barely alive. On her 29th birthday, Townsley was not at home in Alabama. Instead, she was in Minnesota getting treatment at the renowned Mayo Clinic.

Now, several years later, she says she’s still in and out of the hospital with medical complications resulting from those injections. She has yet to return to her normal medications for juvenile rheumatoid arthritis.

Second, compounding pharmacies.

The 2012 outbreak was a wake-up call for the country and for Massachusetts when it came to compounding pharmacies.  

Congress took steps to improve regulations and increase federal oversight. Since the outbreak, 18 states enacted laws that relate to compounding pharmacies, and other states are in the process. However, there's still a lot of variation state by state.

In Massachusetts, there is more oversight and more resources for inspections. Yet, it’s worth noting that there’s still not a perfect system. Compounding pharmacies regularly get calls requesting bulk drugs even when they are not supposed to be making medications in bulk, and Massachusetts has been slow to oversee compounded drugs that come from other states but are given to patients here.

One more big impact, insurance.

According to several pharmacists, insurers have used the 2012 outbreak as an opportunity to reduce their coverage of compounded drugs. So many people’s custom-made medications are now much more expensive. Insurers says these compounded medications are often used unnecessarily and they’re just making sure such medications are only used when absolutely necessary.

5. When the verdict is announced, what happens next?

After the verdict, Cadden awaits his sentencing. His business partner, Glenn Chin, will soon go on trial. He also faces second-degree murder charges.

Chin was the supervisory pharmacist, overseeing the pharmacy’s cleanrooms where the drugs were made. Initially, Cadden and Chin were charged together, but because Cadden’s lawyers have tried to blame Chin, they ended up getting separate trials.

Cadden’s verdict could inform how the federal prosecutors present their case against Glenn Chin. His trial has not been scheduled yet.