Scientists have developed a new procedure to measure levels of the medication HCQ in patients with the rheumatic disease systematic lupus erythematosus.
Hydroxychloroquine was originally used to treat malaria but has also proven effective with rheumatoid arthritis and SLE, the scientists said.
Today it is recommended to all SLE patients since it has capability to protect against flares of the disease. Tests are also being conducted to see if it can also be used to treat the COVID19 infection, they said.
A major disadvantages of HCQ is its side effects which can be avoided, however, if the HCQ dosages is adjusted to each patient. To achieve the protective effect against flares in SLE while also minimising the risk of it's side effects, scientists developed a method that can be used in the medical care system to measure HCQ levels in the blood of SLE patients.
The method, mentioned in the journal Arthritis Research and Therapy, is based on high resolution mass spectrometry.
The researchers went through available data on HCQ measurements. They saw that results from measurements on whole plasma, blood and serum were not comparable with each other.
Kim Kultima associate professor at Uppsala University said, it was shown that there were major difference between different reports and there seemed to be very large differene.
The research team compared the levels of HCQ in serum, plasma and whole blood in SLE patients.They concluded that the levels in whole blood were about twice as high as in plasma and serum. Whole blood analyses were also the most dependable.
The researchers said, One noticeable result, and a very important vision, was that levels in whole blood for patients prescribed the same dosage could differ by upto 15 times between individuals. It indicates a large individual variation in how the medication is metabolised.
One problem pointed out by the researchers is that the services for electronic information on medicinal products in Sweden provide concentration of HCQ in plasma.
The scientists judge that these values provide an inappropriate and inaccurate picture for monitoring medication levels in patients.
The researchers also said, we have to very careful about drawing hasty conclusions about whether HCQ is effective with Coronavirus. What we know today is the analysis method will helpfully lead to better data for providing the right dosages to SLE patients who are prescribed the medication.
They are planning to measure the levels of the medication in the blood of COVID19 positive patients if the substance proves effective.