The United States has provided doses of an experimental antibody drug developed by Mapp Biopharmaceutical to support clinical trials targeting the Ebola outbreak in the Democratic Republic of Congo (DRC), according to a Health Department spokesperson.

The move marks a shift in policy, as the treatment had previously been made available primarily for use within the United States, with limited international access.

Officials from the US Department of Health and Human Services said the drug will now be supplied for compassionate use in Congo as well as to advance ongoing clinical trials in the affected region.

While the number of doses was not disclosed, the department said the objective is to generate data that could support future regulatory review and potential approval of the treatment.

The decision comes as health authorities struggle to contain a rapidly spreading Ebola outbreak in eastern Congo, which has recorded more than 1,000 cases and over 250 deaths.

The World Health Organization (WHO) has warned that the outbreak could become one of the most severe in recent years if response efforts are not significantly strengthened.

The outbreak involves the Bundibugyo strain of Ebola, for which there are currently no approved vaccines or treatments, increasing reliance on experimental therapies under strict clinical trial conditions.

The WHO confirmed that shipments of experimental drugs, including Mapp’s MBP134 antibody therapy and other candidate treatments, are being delivered to support upcoming trials in the region.

The trials are being coordinated with partners in the Democratic Republic of Congo, Uganda, and international research institutions, including the University of Oxford.

MBP134 will be tested both as a standalone treatment and in combination with the antiviral drug remdesivir, developed by Gilead Sciences and widely used during the COVID-19 pandemic.

Another antiviral, obeldesivir, is also expected to be tested as a preventive option in separate studies led by African and international health agencies.

Health officials say vaccine development remains at an early stage, with initial Phase 1 trials potentially beginning as soon as next month in the United Kingdom and possibly Uganda.

Leading candidates include vaccine programs developed by the University of Oxford in partnership with the Serum Institute of India, as well as mRNA-based vaccines from Moderna.

However, experts caution that widespread vaccine deployment in outbreak zones will take time due to manufacturing, safety evaluation, and regulatory approval requirements.

Health agencies warn that conducting clinical trials in conflict-affected regions such as eastern Congo presents major challenges, including insecurity, mistrust among communities, and limited infrastructure.

Despite these difficulties, the WHO says clinical trials are essential to determine the safety and effectiveness of potential treatments and to improve future outbreak response strategies.

The organization emphasized that all experimental therapies must undergo rigorous testing before being approved for widespread use.

The US government has also pledged financial and technical support to Ebola response efforts across Africa, aiming to strengthen containment measures and reduce the risk of cross-border spread.

Health officials say the current outbreak highlights the urgent need for coordinated global action as scientists race to develop effective treatments and vaccines.