What It Means
The findings have helped clinicians optimize how they use IVIG for dermatomyositis patients, Dr. Aggarwal says.
“We knew it works, but we did not know how quickly it works. What’s the plateau? What’s the safety? What’s the tolerability? All of that was extrapolated from the neurology literature, where most of the time the dose was 1 g/kg and not 2 g. So there was a significant lack of understanding of efficacy.”
Now clinicians have the data to know how long to keep trying IVIG. The trial found that it works within six to eight months, and typically within three to four months. So if it is not working after that, it might be best not to continue, Dr. Aggarwal says.
The trial also has allowed clinicians to use the drug more safely and to counsel patients more thoroughly, says Dr. Aggarwal. A total of 282 treatment-related adverse events were seen in 95 patients, most commonly headache, fever and nausea.
“It’s amazing to see that 92% of the reactions, or the side effects, are infusion related. That means they are going to happen, [but] they only are going to happen for the days you are in infusion and a couple of days after it. That’s it,” Dr. Aggarwal says. “When you tell the patient that, it makes a big difference.”
In the study, no pre-treatment was given routinely for infusion-related reactions, such as fever. Patients had to have two infusion reactions before they could receive pre-treatment. With pre-treatment, the drug is better tolerated, Dr. Aggarwal says.
The prime dermatomyositis candidates for IVIG are those with severe, refractory disease or significant dysphagia, as well as those who are pregnant or have a significant chance of becoming pregnant, who have a high risk of infection, who are undergoing treatment or evaluation for a malignancy and those with calcinosis, according to Dr. Aggarwal.
The data have also led clinicians to take greater precautions to prevent thromboembolic events seen with a thrombogenic disease, such as dermatomyositis, and a thrombogenic treatment, such as IVIG.
“Before this trial, I would not worry about somebody’s high risk of thromboembolic events. I would just give it to everybody not really considering the risk factors. But now I first ask: What are the risk factors?” With these study results in mind, Dr. Aggarwal says he would not give IVIG to a patient with a high thromboembolic risk or who has had thrombolic events.
