During the onset of the pandemic, we witnessed how our healthcare system got overwhelmed with the surge of COVID cases. We heard news reports of hospitals turning away patients due to lack of hospital beds and intensive care unit (ICU) facilities. Medical practitioners and pharmaceutical companies turned to repurposing drugs like Remdesivir, now also considered to be limited resource.
“You can see the theme here—everything that we have is limited in quantity,” says Dr. Charlle Sy, project lead of a study that De La Salle University (DLSU) conducted on the proper distribution of COVID antivirals. Sy and Dr. Kathleen Aviso, co-project lead, presented their findings in a webinar Thursday morning. “Even if we want to distribute these [COVID] drugs, even if we want to accommodate patients, there’s simply not enough supply to go around.”
Sy says this became a topic of discussion among DLSU researchers during the enhanced community quarantine. “How do we actually allocate these resources? Do we give them to the most vulnerable—those who would probably be are under the senior aged category? Or do we give them to those that would have the highest chance of surviving the disease? These were questions that we wanted to address,” she shares.
Being in the field of engineering, Sy, Aviso and company thought there must be an analytical approach that would allow the government to address this issue in a more systematic manner. This is the reason they decided to formulate a mathematical model to help answer these questions.
Back in April, out of curiosity, their team of 12 researchers from DLSU decided to develop a computer program (an operations research model) for the allocation of antiviral drugs in case of shortage. The said study, which has already been published in a peer-reviewed journal “Clean Technologies and Environmental Policies,” remains the only one in the world that documents a program to allocate COVID-19 drugs.
The team factored in four data inputs or assumptions in their model: 1) infection severity levels with corresponding care; 2) case fatality rates of patients at a given severity level, with or without appropriate care; 3) regions with known incidence rates and healthcare resources; and 4) efficacy of antivirals.
Sy presented a diagram that suggests a practical approach to optimally allocating available antiviral drugs: to base it on the patients’ severity of case (critical, moderate and mild).
“We assume that if you are able to get these antiviral drugs, there is a chance that the level of severity will get downgraded,” says Sy.
The mathematical model also considered a few other things. One, whether or not patients have access to hospital resources and the type of hospital resources they have access to. Two, the capacity limits (or level of efficacy) of the anti-viral drugs and the healthcare facilities (the normal hospital beds and the ICU facilities). They also looked into the possible constraints—that there are people who are able to get appropriate care and people who are not able to get appropriate care. Their main objective, she says, is to avoid fatalities from these two classifications.
The mathematical formulas are quite technical for an ordinary person to understand. But an important takeaway from their research, Sy points out, is that “homecare increases with the drug availability.” As severity levels are downgraded, hospital resources are freed up.
“You do not overwhelm the healthcare system because people could now afford to self-treat at home, or probably they could remain in the normal hospital beds rather than use up the entire ICU capacity, which we saw in the early parts of this pandemic,” says Sy.
As their next step, the team, under the DLSU’s Data Science Institute, will develop more accessible codes or freeware that can be used by anyone, and also to translate their study on antiviral allocation to vaccine allocation “because we believe that this is a problem that needs to be tackled in an analytical way,” stresses Sy.
Dr. Aviso assures that they intend to expand the models so that these can integrate other aspects and parameters that are more relevant with vaccines. “These are still in the works. We intend to complete this project in three months,” she says.
Dr. Ador Torneo, Director of the Jesse M. Robredo Institute of Governance, a private research and training organization based in the DLSU, points out that there are about 70 hospitals under the auspices of the Department of Health. As far as DOH-run hospitals and the local government run hospitals go, drug allocation is decentralized, he says. In other words, “there is no one policy that actually determines how drugs should actually be allocated.”
He says he was looking at the Philippine budget for health for 2021 and found there is no explicit amount allocated for COVID-19 drugs. “There is around P2.5 billion allocated for COVID-19 vaccines which should cover 3 million priority groups. Take note that the Philippine population is 109 million.”
According to Torneo, many hospitals now allocate COVID-19 drugs on a compassionate use basis—meaning, it is the doctors and hospitals that decide which patient needs the drug (mostly those in critical care). But he says the models presented by the DLSU engineers could help so that our health resources—especially the COVID antivirals and vaccines—could be used optimally in the future.