I'm a little surprised they're starting new trials of hydroxychloroquine at this stage, especially on older people - in which group its well-known side effects (such as prolonging the QT interval leading to the risk of potentially-fatal heart arrhythmias) are even more dangerous.
I'm even more surprised that they're considering combining it with azithromycin since it is also known to prolong the QT interval, thus exacerbating these dangerous side effects even further.
Medical authorities in several countries (including Sweden, Brazil, USA and France) have advised against using hydroxychloroquine and/or discontinued trials of it before completion because of the adverse effects it was having on the trial participants. No properly-conducted, peer-reviewed study has yet has shown any benefit from hydroxychloroquine, either on its own or in combination with azithromycin. The one French study that did claim beneficial effects has since been roundly condemned as flawed and disowned by the journal that published it.
The French authorities even went so far as to say that the use of hydroxychloroquine to treat CoVid-19: