Effect of Nucleic Acid Analog Administration on Fluctuations of Albumin to Globulin Ratio in Cats with Feline Infectious Peritonitis

Background: Feline infectious peritonitis (FIP) is a fatal feline disease classified as either effusive (wet), non-effusive (dry), or a mixture of both forms (mixed). The anti-FIP therapeutic effect of Mutian and molnupiravir, two drugs whose active ingredient is a nucleic acid analog, has been confirmed recently. Methods: Of the cats with FIP, we observed a total of 122 and 56 cases achieved remission after administration of Mutian and molnupiravir as routine treatments, respectively. Changes in clinical indicators suggested to be correlated with FIP remission (weight, hematocrit, and albumin to globulin ratio) before and after the administration of each drug and during follow-up observation were statistically compared for each FIP type. Results: In all three FIP types, administration of either Mutian or molnupiravir resulted in statistically significant increases in these indicators. Furthermore, the effect of Mutian on improving the albumin to globulin ratio was not observed at all in wet FIP, as compared with that of molnupiravir, but statistically significant in mixed and dry (P0.02 and P0.003, respectively). These clinical features were all due to differences in fluctuations of circulating globulin levels. Conclusions: These results indicate slight inflammatory responses might be elicited continuously by residual feline coronavirus non-disappeared through molnupiravir treatments.