QCOSTARICA – The Caja Costarricense de Seguro Social (CCSS) is ready to begin its second scientific trial with equine serum in hospitalized patients with covid-19.
The institution announced Friday morning at a press conference that the protocol has already been approved by the ethical-scientific committee (CEC).
“That second protocol, designed to optimize the dose for covid patients, is really about to start. An analysis had to be made of the results of the first protocol, already concluded,” said Román Macaya, executive president of the CCSS.
Macaya, however, did not give a date when the tests will begin.
“A new authorization had to be requested from the scientific ethics committee and some external collaborations (from George Manson University) that had to be given (for example, neutralizing potency tests for new batches),” stated Macaya.
“The good news is that the second protocol has already been approved by the ethics committee and I hope it is starting soon, which will be announced,” he added.
According to researchers Alfredo Sanabria and Willem Buján, who were in charge of the previous clinical trial and who would also take over the second, said in a previous interview, there are changes between one research design and another.
For example, the second protocol presents new doses of serum (and different levels in these), other types of patients and the inclusion of a comparator arm, that is, a group of patients who do not receive this serum and who would serve as control.
Regarding the doses, in the first study, conducted with 27 people hospitalized with Covid-19, all participants were administered 500 milligrams of equine antibodies. This study was carried out in September and the patients were followed for three months.
This second study would be with about 100 patients in hospitalization conditions who are in serious or critical condition.
“(The protocol) incorporates changes in the doses to be administered, this modification considered both information obtained from the previous protocol and recent information at the international level. Aspects specific to each possible participant such as weight (weight dose) were also taken into account,” the researchers pointed out.
The latter (the weight dose) is so because a patient weighing 45 kg may not necessarily react in the same way as one weighing 80 kg to the same dose. This is part of what will be explored with the new study.
In addition, only one of the sera designed by the Clodomiro Picado Institute will be used.
This option works with the S1 protein or spike protein, located in the corona of the virus. It binds to the cellular receptor and allows the virus to enter the human cell. However, this serum was found to neutralize the protein, so it could not enter new cells.
Alberto Alape, director of the ICP-UCR, indicated in a previous interview that both sera showed very similar efficacy, but the other version, which combined several virus proteins, was more expensive to produce, so only S1 will be used.