The development of new treatments and preventives to combat the lethal Ebola virus has been slow, marked by caution at public health agencies to approve testing of high-risk compounds, and reluctance of biopharmaceutical companies to invest in a field with limited market potential. All that has changed now, as thousands of people have been sickened by the virus, and the death rate has escalated. The risk of harm from an untested treatment now is much less alarming than the prospect of infection, and the potential benefit of any effective treatment outweighs the need for regulatory caution.
Thus international and national authorities are working hard to facilitate access to experimental drugs and vaccines, despite a long history of distrust related to studying experimental treatments in Africa and other developing regions. Sponsors often face charges of using poor patients to test products that later will be unaffordable and unavailable. Authorities also question whether severely ill patients can make informed decisions about treatment options amid community fears of medical treatment. Vaccines raise added concerns, as they require widespread testing over long periods, often in healthy individuals and children. While the possibility of severe side effects from test drugs can generate a backlash against potential treatment, withholding therapy raises even more serious questions.
An important step was for the World Health Organization (WHO) to declare it ethical to use unproven therapies to try to contain the growing Ebola outbreak in West Africa. FDA similarly permitted a small biopharma company to distribute an experimental product that had been put on clinical hold due to concerns about a possible serious side effect.
These actions, though, raise similarly difficult questions about how to distribute the very limited supply of an experimental drug. Some experts cite the importance of treating children first. Others believe that patients with access to effective care are more likely to recover, making that a factor in using scarce medical resources.
Healthcare workers often get top priority, on the basis that doctors and nurses are needed to care for the sick, and that the prospect of treatment may encourage critical professionals to volunteer for service. But the treatment of two Westerners with the potentially effective drug Zmapp raised protests that the therapy was not available to sick Africans.
One rationale for treating health professionals is that they are familiar with protocols and can understand the risks and the informed consent process. Treatment in a hospital setting also is more likely to support scientific assessment of an experimental regimen. One area of agreement is the importance of collecting and evaluating data on the safety and efficacy of experimental drugs used during the outbreak, and to share that data with all affected parties.
Researchers are continuing to assess factors related to the recovery of the two health workers who received Zmapp, acknowledging that they don’t know if that good result is are due to the drug, to effective care, or to other health factors. Treatment with this monoclonal antibody therapy produced by tiny Mapp Biopharmaceutical of San Diego may facilitate FDA approval of initial clinical trials, once the company can rebuild its exhausted supply.
Tekmira Pharmaceuticals of Canada may gain important safety information on its test product, TKM-Ebola, now that FDA converted a “full clinical hold” to a “partial hold” on its phase 1 trial, which permits the company to provide the drug to infected patients – but not to healthy volunteers — due to concerns about a potentially serious side effect.
While US and international authorities grapple with these ethical and logistical issues, manufacturers are struggling to ramp up production. Three centers in the US have capacity to quickly scale up production of a vaccine or therapy in response to an epidemic or biological threat and may be tapped to produce candidate vaccines.
A low-priority Ebola vaccine development project at GlaxoSmithKline’s Okairos unit now expects to move from preclinical development to clinical trials this year. Several small biotech firms are looking to gain needed funding to revive abandoned Ebola vaccine development programs. But optimistic statements from biopharma companies raise the risk of appearing “opportunistic” and “self-promoting,” noted biotech commentator Adam Feuerstein in his “The Street” blog. A lethal outbreak of contagious disease provides an opportunity for biopharma companies to demonstrate their capacity to respond with innovative therapies, based on ethical and scientific factors, as opposed to the potential for financial gain.
by Jill Wechsler