Dengue vaccine: Ex-FDA chief defends circular removing post-marketing surveillance
MANILA, Philippines – The former head of the Food and Drug Administration (FDA) on Wednesday, December 13, defended a 2013 circular he issued that allowed for the dengue vaccine to get a certificate of product registration (CPR) even without the conduct of a post-marketing surveillance.
Former FDA Director General Kenneth Hartigan-Go was mentioned in e-mails by a witness being handled by the Volunteers Against Crime and Corruption. The witness claimed that “dengvaxia got a super-quick certificate of product registration from FDA supervised by Usec Kenneth Hartigan-Go.”
During Wednesday’s committee hearing at the House of Representatives, Melody Zamudio, the officer-in-charge of FDA’s Center for Drug Regulation and Research, said they granted a 5-year CPR for the monitored release of Dengvaxia after Sanofi submitted phases 1 to 3 of the clinical trials.
They did not require phase 4 before issuing the CPR because according to Zamudio, phase 4 is part of the post-marketing surveillance.
“There’s a circular issued by then FDA Director [General] Kenneth Hartigan-Go that post-marketing surveillance need not be conducted among Filipino people. Previously, we require 3,000 patients under monitored release, but for that circular, it's not anymore required. We accept global status after the issuance of CPR as part of post-marketing surveillance
Oriental Mindoro 1st District Representative Doy Leachon then asked Hartigan-Go if the questions surrounding the dengue vaccine would be answered if only phase 4 of the clinical trials were conducted.
"The memo of the post-marketing surveillance was prepared in 2013 – two years before dengue vaccine. The rationale [was] to provide stronger, robust FDA strategy in their pre-market approval process. It is precisely the patients’ welfare that we had in mind when we crafted this circular in consultation with our technical team and with the stakeholder in industry,” Hartigan-Go explained.
According to him, prior to the 2013 circular, the post-marketing surveillance was “very deficient.”
“Nakita po namin na inaabuso po ng industirya at ng mga doktor, dahil nababayaran to do a 'monitoring study' and they submit data that are not good enough for us to be able to detect. Dahil po sa statistics, 3,000 patients, 'di makukuha ang adverse reaction,” he added.
(We saw that the industry and the doctors are abusing it, because they are paid to do a 'monitoring study' and they submit data that are not good enough for us to be able to detect. Because of statistics, 3,000 patients, we can't get any adverse reaction.)
Hartigan-Go then enumerated the other mechanisms and strategies they put in place in lieu of the post-marketing surveillance, such as requiring periodic safety update reports and submission of risk management plans,
"Outside of this memo, meron pang (there are) other strategies in keeping with Republic Act 9711. We created a pharmacovigilance unit that can evaluate all cases from periodic safety,” he added.
But Dr Tony Leachon, who has opposed the implementation of the dengue vaccination program as early as 2016, said the removal of a post-marketing surveillance program “opened the floodgates” to a new drug that may not be safe.
"This is not alluded to him [Kenneth Hartigan-Go], but when post-marketing surveillance program is removed, then you open the floodgates to a new drug that may not be safe for the market because post-marketing surveillance would entail a doctor-patient relationship,” said Leachon, the elder brother of Doy Leachon.
Dr Tony said the doctor-patient relationship was eliminated when the health department decided to conduct a mass vaccination. He noted that only when a product has been deemed safe should the Formulary Executive Council (FEC) be consulted.
“But in this particular issue, even FEC required Sanofi and [Department of Health] to submit a [post-marketing surveillance], and this is not actually achieved prior to mass vaccination,” he said.
Rappler earlier reported that the move to include vaccine Dengvaxia in the national vaccination program did not have the imprimatur of the FEC – the panel of medical experts that was tasked to review its safety, effectiveness, and even its cost-effectiveness.
Health Secretary Francisco Duque III suspended the program on December 1, or a day after French pharmaceutical giant Sanofi Pasteur revealed that Dengvaxia could cause more severe cases of dengue if administered on a person who had not been previously infected by the virus.
The hearing is still ongoing as of this posting. – Rappler.com