At the 33rd European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) 2023 conference in Copenhagen, Denmark, a year-long review of infectious diseases discussed some of the most important findings of 2022, relating to viral, bacterial, and fungal infections.

More than two years after the start of the pandemic, Covid-19 remained a key area of research interest throughout 2022. A retrospective study provided the first real-world data on the use of antiviral therapy Paxlovid (N-Rtv) to treat Covid-19 and its impact on hospitalisations among adult patients between March and August 2022. Decreases in hospitalisations, ER visits, intensive care unit (ICU) admissions, and deaths were observed among the 10,000 patients treated with Paxlovid relative to the 11,000 untreated patients. Of the patients treated with Paxlovid, 283 reported an ER visit (3.9%), 47 had a Covid-19-related hospitalisation (0.7%), and there were two patient mortalities (<0.1%). Compare this to the untreated group which reported 437 ER visits (4.7%), 109 Covid-19-related hospitalisations (1.2%), and 15 patient mortalities (0.2%). This data demonstrates strong evidence of the therapeutic benefit of Paxlovid (N-Rtv) during the Omicron BA.4 and BA.5 subvariant period. Further data on Paxlovid’s therapeutic potential in Covid-19 is likely to be released in the coming years. GlobalData confirms there are currently 14 ongoing and two planned trials on Paxlovid, extending into 2028.

Another key study from 2022 focused on pre-exposure prophylaxis (PrEP) for HIV. HIV is disproportionately represented in women – particularly those in sub-Saharan Africa. In a Phase III study with more than 3,000 female participants at high risk of infection, patients were either administered cabotegravir (CAB group) or tenofovir disoproxil fumarate/emtricitabine (TDF/FTC; TDF group). TDF/FTC (sold under the brand name Truvada) has been approved in the US since 2004, and World Health Organization (WHO) recommended as a HIV PrEP since 2015. Cabotegravir (sold under brand names Apretude and Vocabria) was approved for use in the US in 2021. In the study, incident HIV cases for those in the CAB group were 88% lower than those in the TDF group. In comparison to the standard of care (TDF/FTC) taken on a daily basis, CAB given every eight weeks was found to be more effective in preventing HIV in women at high risk of infection and was considered to be safe and well tolerated. In 2022, cabotegravir was approved as PrEP for HIV prevention in Zimbabwe – its first approval in a low- and middle-income country.

A Phase III trial for SER-109 – an oral microbiome therapeutic in development for Clostridium difficile infections (CDIs) – also reported promising data in 2022. CDIs most commonly result from antibiotic use and lead to gastrointestinal symptoms such as diarrhoea. Patients who were at high risk of recurrent CDIs (≥3 infections in the past year) were targeted for this study. Of the 89 patients taking SER-109, only 12% developed an infection (n=11). By comparison, of the 93 patients taking a placebo, 40% developed an infection (n=37). This study demonstrated that SER-109 was superior to a placebo in reducing the risk of recurrent CDIs. GlobalData forecasts that SER-109 will launch in the US this year and will reach $375m in sales in this market by 2028.

Among fungal infections, cryptococcal meningitis has received much attention, as its pathogen – Cryptococcus neoformans – was reported as a fungal priority pathogen in 2022 by the WHO. Cryptococcal meningitis is the leading cause of HIV death in sub-Saharan Africa. A phase III study of single-dose liposomal amphotericin B, plus flucytosine and fluconazole, was conducted among 814 HIV patients in Africa with cryptococcal meningitis. The ten-week endpoint announced 24.8% mortality in patients receiving the single-dose liposomal amphotericin B, plus flucytosine and fluconazole. The active comparator group which had been administered amphotericin B deoxycholate, plus flucytosine and fluconazole, announced 28.7% mortality. This treatment was deemed non-inferior to the current WHO-recommended treatment, and it was associated with fewer adverse events. Continued research of cryptococcal meningitis is of great importance, as GlobalData confirms there are currently 11 ongoing trials and ten planned trials for this fungal infection.