PharmaMar Soars 21% After Mouse Data Confirm Drug's Efficacy Against COVID

By Reuters Staff

January 27, 2021

MADRID (Reuters) - Shares in Spanish pharmaceutical company PharmaMar spiked over 20% on Tuesday after it cited a paper published in the journal Science that confirmed "potent preclinical efficacy" of its drug Aplidin against COVID-19.

A study carried out in vitro and in mice by a team of scientists in New York, San Francisco and Paris showed Aplidin (plitidepsin) leads to a reduction of viral replication, resulting in a 99% reduction of viral loads in the lungs of animals, the researchers reported (

The drug, approved in Australia for the treatment of multiple myeloma, blocks a host protein associated with the COVID-19 virus. Toxicity of the drug is well known and the doses used in COVID-19 trials are well tolerated in humans, the company said.

"When we infected animals and we treated them with the adequate dose of plitidepsin, an extraordinary reduction of the viral load is produced," Pablo Aviles, head of nonclinical toxicology and pharmacology at PharmaMar, told Reuters TV.

The drug began early-stage clinical trials against COVID-19 last year. In April, plitidepsin was among several existing drugs flagged for their potential antiviral activity in a multidisciplinary study of host proteins that interact with the SARS-CoV-2 virus (;

PharmaMar said it was in talks with various regulatory agencies - the most advanced ones being with the Spanish and British regulators - to start Phase III trials. They are deciding how many patients should be included in the trial.

"At first we are not targeting ICU patients, there will be hospitalized patients, but doctors are collaborating with us to identify the different phases a sick person goes through, and determine which would be ideal to focus on to produce the best results we can get from plitidepsin," he said.

PharmaMar shares were up 21% at 106 euros in late trading on Tuesday, heading for their strongest close since early November and leading the Spanish Ibex-35 stock index, after retreating slightly from the day's peak of 110 euros.