Neutralizing antibody responses against SARS-CoV-2 in patients with plasma cell disorders who are on active treatment after two doses of mRNA vaccination.

Many patients with plasma cell disorder (PCD) on active treatment with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) require hospitalization, with an increased mortality rate over healthy adults. The FDA approved two mRNA vaccines against SARS-CoV-2: BNT162b2 and mRNA-1273. To assess the efficacy of vaccination in patients with PCD, retrospectively, we identified all patients on active treatment. A total of 149 patients were included. Neutralizing antibodies (NAbs) levels against SARS-CoV-2 adequate, intermediate, and no response were observed in 42%, 32%, and 26%, respectively. Low NAbs were seen in patients on daratumumab combinations or anti-BCMA therapy, low lymphocytes, and low IgG levels. Twenty-three (15%) patients have SARS CoV-2, while 8% required hospitalization, majority of these patients had intermediate or no response based on NAbs levels. Therefore, checking NAbs may be clinically helpful in identifying patients' responses. Further prospective studies should ascertain the value of a third vaccine dose in this population.

Effect of vaccination against leptospirosis on the frequency, days to recurrence and progression of disease in horses with equine recurrent uveitis.

OBJECTIVE: To evaluate the effect of vaccination against leptospirosis on frequency and days to recurrence of uveitis and progression of disease in horses with equine recurrent uveitis (ERU). ANIMALS: Forty-one horses with ERU. PROCEDURE: Horses were randomly assigned to experimental (vaccinated) or control groups. Vaccine containing six serovars of Leptospira or placebo was administered, an ophthalmic examination performed and blood samples drawn on days 0, 28, 180 and 365. Antibody titers were measured against each serovar. Recurrence of uveitis was verified by ophthalmic examination. Results of the initial and final ophthalmic examinations were compared and progression of disease defined as an increase in extent of synechiae, or development of new or progression of an existing cataract. RESULTS: Vaccination increased the average geometric mean serum antibody titer from 225 on day 0, to 4077 and 593 on days 28 and 180, respectively. After the second vaccination, days to first recurrence was significantly longer (median 126 days; range 24-231 days) when compared with controls (median 86 days; range 14-192 days, P=0.04). Recurrence of ERU was observed among 7/20 (35%) vaccinated horses and 12/21 (57%) controls; however, this difference was not statistically significant (P=0.061, OR 0.25, 95% CI 0.06, 1.07). More horses in the experimental group 13/20 (65%) experienced progression of disease when compared with controls 12/21(57%); however, this difference was statistically nonsignificant (P=0.35). CONCLUSIONS: Vaccine significantly increased days to recurrence, but failed to slow the progression of disease. These data do not support the use of vaccination against leptospirosis as adjunct therapy for the routine treatment of horses with ERU.