Discussion:
This study included 62 subjects who tested positive for COVID-19 and
received Sotrovimab infusion within an average of 4 days of symptoms
onset between November 2021 and March 2022 at AUBMC. To our knowledge,
this study is the second one from the Middle East, the first one was
conducted in United Arab Emirates (UAE) [16], describing real-life
experience with Sotrovimab as treatment in patients with COVID-19. And
it is the first study that includes a high proportion of cancer
patients.
Most of our subjects were classified as tier 1 priority as per NIH
criteria as patients in this tier were at the highest risk for disease
progression. As compared to other cohorts in the earlier Sotrovimab
clinical trials [12, 16-17], more patients in our study had
hematological malignancies and/or were receiving active chemotherapy.
Moreover, more than 50% (63.4%=27.9+35.5) of our patient population
had cancer, whether hematological malignancy or solid organ malignancy
and those are considered high-risk subjects and at risk for severe
COVID-19 disease and death [18]. In the study from UAE only 1% of
the subjects in the Sotrovimab group were immunosuppressed [16].
Whereas in the study by Aggarwal et al 24.9% of the subjects who
received Sotrovimab were immunosuppressed [19].
Before the use of Sotrovimab, COVID-19 was associated with serious
complications in cancer patients. In fact, the percentage of
hospitalization among cancer patients who were infected with COVID-19 in
the U.S varied between 25.2% and 33.7% [20]. And, in a study from
China, the percentage of clinical deterioration and intensive care unit
(ICU) admission in this patient population was reported as 39%
[21].
In our cohort, we found that 21% of the subjects required
hospitalization after receiving Sotrovimab, and 21 % had clinical
deterioration within 24 hours of Sotrovimab infusion even though most of
our subjects were cancer patients. Those rates were higher compared to
the previously published trials [12, 19]. In the study from UAE, the
overall hospitalization was 3.9%, and the percentage of critical
disease progression was 0% [16]. However, patients who received
Sotrovimab in the UAE study were selected based on a risk stratification
criterion with at least one risk factor for disease progression, and the
most prevalent risk factor for disease progression among patient who
received Sotrovimab infusion was overweight 36% followed by HTN 20 %
[16] and both percentages were much lower than the risk factors
percentages in our cohort where 63.2 % of our subjects were obese and
56.5 % had HTN.
In a recent study from Sao Paulo Brazil the mortality rate among cancer
patients who were hospitalized for COVID-19 was 49% without Sotrovimab
[22]. The mortality rate in our study was much lower at 6.5% but
still higher than the mortality rate among patients who received
Sotrovimab in the studies that included less cancer patients such as the
study from UAE [16] and that from Aggarwal et al [19].
The difference in the findings is mainly due to the overall proportion
of immune suppressed subjects in the various studies and whether the NIH
prioritization criteria were applied or not.
In our series, no adverse events related to Sotrovimab infusion were
reported compared to 2% Sotrovimab related adverse events in the COMET
ICE clinical trial and 10% in the TICO trial [12, 17].
Another point of relevance in this study is the very high compliance
with the set criteria for use of Sotrovimab developed at our institution
by the concerned stakeholders including ID specialists and pharmacists.
Despite the chaos in Lebanon and the many challenges faced in all health
care institutions [14], the Antimicrobial Stewardship Program at
AUBMC has high level expertise in developing institutional policies, and
guidelines for various diseases including COVID-19 with a tight control
on the use of various agents including the monoclonal antibodies. The
program follows patients closely to ensure adherence and compliance to
various medications use.
Our study has several limitations. First, it is a retrospective study
and not all the data needed was available in the reviewed charts. Also,
the sample size is small, given the limited number of available
Sotrovimab doses. It included vaccinated patients, and vaccination was
not homogenous among the cohort and the subjects received different
types of vaccines. In addition, our study was not homogenous in terms of
management and treatment options for COVID-19 infection (concomitant use
of remdesivir, steroids, and tocilizumab). As a result, the
generalizability of the findings of the study is limited. Another
limitation is the fact that the SARS-CoV-2 variant type of each subject
was not identified; this information would have been important in light
of several reports of a decreased efficacy of Sotrovimab against Omicron
variants of COVID-19 [13].