Is Tezepelumab effective for eosinophilic asthma?

Hi doctor,

My 25-year-old son has been on Tezspire for severe eosinophilic asthma for five months with concerning developments. Initially, his breathing improved dramatically. He went from weekly urgent care visits to no rescue inhaler use for almost two months. However, he's developed increasingly troubling symptoms: severe joint pain in his knees and ankles that makes walking difficult; recurring low-grade fevers after each injection; unexplained rash across his torso and back; and most alarmingly, three episodes of blurred vision with intense headaches. His pulmonologist ordered basic bloodwork, which showed elevated inflammatory markers but offered no explanation or monitoring plan. His asthma symptoms have begun worsening again despite continuing the medication. His next injection was scheduled for the next day, and we were conflicted. Could these be serious immune-mediated side effects? Should we seek a rheumatology evaluation before the next dose? We're terrified of stopping the only medication that initially helped his breathing, but equally frightened by these new concerning symptoms.

Thanks.