9JUN

Only Ebola treatment still cannot dose

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As of WHO's 29 May bulletin, the MBP134 and remdesivir trial, the only experimental Bundibugyo treatment, had still not been authorised to dose a single patient. A new $62 million vaccine coalition needs 12 to 18 months to reach human trials.

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Key takeaway

The only experimental Bundibugyo treatment stayed unauthorised on 29 May; a new vaccine push needs 12 to 18 months.

WHO bulletin DON605 confirmed on 29 May that the MBP134 and remdesivir trial, the only experimental Bundibugyo treatment, had still not been authorised to dose a single patient ¹. MBP134 is a monoclonal antibody cocktail, a laboratory-made mix of immune proteins designed to bind the virus; remdesivir is a broad-spectrum antiviral used clinically during COVID-19. No licensed vaccine or treatment exists for this Ebola species at all.

The three approved Ebola products, Ervebo, Inmazeb and Ebanga, all target the Zaire species and give no cross-protection . The MBP134 trial had been awaiting DRC and Uganda regulatory clearance since 20 May , so six people moved from the confirmed-living column to the confirmed-dead column during the eight-day gap. The contrast with eastern DRC in 2018-20 is sharp: that Zaire outbreak at least had Ervebo for ring vaccination, inoculating the contacts of each case to wall the virus off.

STAT News reported on Monday 1 June that a new Coalition will fast-track three Bundibugyo vaccines with $62 million in funding ². It will not change this outbreak: a vaccine starting now needs 12 to 18 months to reach even early human trials. The countermeasure gap is structural rather than accidental, and the Pandemic Agreement's pathogen-sharing annex that might have funded earlier work was deferred to 2027 .

Deep Analysis

In plain English

When a new disease outbreak happens, doctors need treatments, meaning medicines that can help sick people survive. For this Bundibugyo Ebola outbreak, the only experimental treatment being considered is a combination of two drugs: MBP134, an antibody therapy developed by a company called Mapp Biopharmaceutical, and remdesivir, an antiviral used during COVID-19. The problem is that neither drug has been formally approved for use in DRC or Uganda. Before doctors can give them to patients, the governments of both countries must each run their own review process to confirm the drugs are safe enough to try. That review has been pending since 20 May, and as of 29 May no patient has received either drug. Meanwhile, a separate group announced on 1 June a $62 million effort to develop vaccines specifically for Bundibugyo. But vaccine development takes 12 to 18 months at the fastest, so a vaccine will not be available for this outbreak.

Deep Analysis

Root Causes

The MBP134 approval delay has two structural causes that are independent of the outbreak timeline. First, Bundibugyo ebolavirus had only 169 combined human cases across its entire pre-2026 clinical record (131 in 2007 Uganda, 38 in 2012 DRC). No regulatory agency has ever run an EUA review for a Bundibugyo-specific therapeutic, which means there is no pre-negotiated protocol or precedent the DRC and Uganda DPLM can apply by analogy. The review is, in regulatory terms, a first-draft process.

Second, the WHO Pandemic Agreement's Pathogen Access and Benefit-Sharing (PABS) annex, which was meant to create automatic benefit-sharing obligations (including accelerated regulatory review) when countries share virus samples, was deferred to WHA80 in 2027.

Without PABS in force, there is no binding international obligation on the drug developer or the WHO to share MBP134 data with DRC and Uganda in a format that expedites their national review. The legal architecture that would short-circuit this delay does not yet exist.

What could happen next?

Risk
Every additional week without a licensed or emergency-authorised treatment means all patient care in DRC and Uganda remains limited to supportive therapy: fluids, oral rehydration, and isolation.
Precedent
The MBP134 approval delay is generating institutional pressure for WHO and the Pandemic Fund to negotiate pre-positioned emergency-use frameworks for candidate therapeutics during future PHEIC declarations, as a complement to the unresolved PABS mechanism.

Source Landscape

This story draws on neutral-leaning sources

Primary parallel: During the 2018-20 Kivu Zaire Ebola response, ZMapp (the first candidate monoclonal antibody therapy) was available in limited supply but took six weeks to receive DRC regulatory authorisation for compassionate use, by which time the PALM trial had already demonstrated that Inmazeb and Ebanga were superior alternatives.

The six-week ZMapp window cost the response a higher-efficacy treatment option during the critical early amplification phase. MBP134 is now in an analogous position: applications pending since 20 May, outbreak already at 1,040 cases, no dosing yet.

Counter-parallel: Uganda's 2022 Sudan ebolavirus response demonstrated that a government can create a parallel fast-track approval process for an unapproved candidate (the Sabin ChAdOx Sudan vaccine, used under emergency protocol) within 11 days of outbreak declaration.

The DRC Ministry of Health does not have an equivalent pre-agreed emergency regulatory framework for therapeutics, and the DRC's national drug regulator, the DPLM (Direction de la Pharmacie, du Médicament et des Plantes Médicinales), has a documented backlog from COVID-era regulatory submissions.

Consensus view: Florian Krammer at the Icahn School of Medicine at Mount Sinai, writing in the context of filovirus countermeasure pipelines, has noted that non-Zaire Ebola species have been structurally neglected because both the 2018-20 Kivu response and FDA approval processes were centred on Zaire ebolavirus, the only species with sufficient commercial case-volume to justify large Phase 3 trials.

MBP134's cross-species breadth in animal models, including 100% protection at eight days post-infection, made it the most advanced candidate applicable to Bundibugyo, yet the absence of any prior clinical dosing in humans means DRC and Uganda regulators are being asked to approve a first-in-human emergency-use protocol in the middle of an expanding PHEIC, a regulatory request with no direct precedent for this species.

Counter-view: The WHO R&D Blueprint team and CEPI researchers have argued in the NEJM correspondence space that the precedent from COVID-19 emergency-use authorisation (EUA) processes, where regulators in multiple low- and middle-income countries issued EUAs for mRNA vaccines within days of WHO prequalification, shows that regulatory approval timelines can compress to under two weeks when institutional will is present.

The delay since 20 May is more likely institutional-capacity and paperwork-bandwidth than principled regulatory caution.

Key tension: Whether the DRC and Uganda regulatory bodies have the staffing and legal authority to run concurrent EUA review processes during an active PHEIC, or whether the approval pathway requires a sequential national-level process that cannot be accelerated without new emergency-decree powers.

First Reported In

Update #5 · Ebola money arrives, the cure does not

World Health Organization· 2 Jun 2026

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Causes and effects

Caused by

Ebola drug trial awaits DRC, Uganda nod

The MBP134 and remdesivir trial was already awaiting approval on 20 May (ID:3598); DON605 confirmed it had still not been authorised a week later.

Occurred 20 May 2026

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No vaccine, no treatment, no MCM

No licensed MCM exists for Bundibugyo (ID:3362), making MBP134 the only experimental option and the approval delay the only barrier to dosing.

Occurred 17 May 2026

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WHO defers vaccine-sharing pact to 2027

The PABS deferral to 2027 (ID:3597) means no international vaccine-sharing mechanism exists to accelerate the countermeasure pipeline that the $62m coalition is trying to build.

Occurred 19 May 2026

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This Event

Only Ebola treatment still cannot dose

Six confirmed patients died in the eight-day window during which the one available experimental treatment remained unauthorised.

Led to

$112m for vaccines, none for the wards

MBP134 and remdesivir remaining unauthorised as of 1 June continues the persistent treatment-access gap documented since 29 May

Occurred 1 Jun 2026

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Different Perspectives

World Health Organization

WHO's DON606 recalibration to confirmed-only reporting gives the clean baseline the CDC model rests on, but the apparent fall from 1,040 to 534 carries misinterpretation risk WHO communications have not pre-empted. The PABS deadlock ahead of IGWG7 and continuing MBP134/remdesivir assessment without authorisation make WHO the body most able to accelerate the two decisions that could change the outbreak's trajectory.

European Union (ECDC)

ECDC's Week 23 CDTR tracked four simultaneous non-Ebola signals: the Dermatophilus congolensis novel-transmission cluster across France, Germany and Spain; a 4.2-fold malaria surge in Mayotte; the Salmonella ST2045 multi-country cluster; and two new Saudi MERS cases. The continental early-warning layer is carrying a full multi-pathogen picture while Bundibugyo dominates headlines.

Uganda

Uganda's 19 confirmed cases are concentrated in Kampala and Wakiso, an urban cluster that applied the 2022 Sudan-ebolavirus playbook; the Bwera border laboratory shortens cross-border confirmation to same-day. Uganda's regulatory authority must co-sign before MBP134 or remdesivir can dose any patient.

Democratic Republic of the Congo

Kinshasa shares Bundibugyo sequence data in real time with no treaty-guaranteed access to the vaccines that data informs, and its health minister called the US entry ban discriminatory while negotiating an early lift. DRC accounts for 515 of 534 confirmed cases and faces IS-controlled access blockades in Mambasa that health authorities cannot resolve.

United States (HHS/CDC)

HHS expanded the Ebola entry ban to green-card holders on 5 June, widening a restriction expiring around 17 June against WHO advice. The CDC simultaneously published the R0=2.51 modelling, the sharpest analytical contribution to the response, from a federal bench that holds the NIH and acting CDC director roles in one person.

Imperial College London / Cori and Ferguson

Anne Cori and Neil Ferguson place the case-fatality ratio at 30 to 40 per cent and read the 6.8-to-1 suspected-to-confirmed ratio as evidence that the laboratory figure understates true lethality. Many people die before a swab reaches them.