@sjc123
I've been taking weekly Actemra injections for a year and a half, and my CRP and ESR values are like yours, 0 and 1. Here is an explanation of why the values are so low and why you can't trust them (from Google AI):

"Does Actemra cause misleading ESR and CRP values?

Yes, Actemra (tocilizumab) causes significantly lower and often "misleading" C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) values. Because Actemra works by blocking the IL-6 receptor—a key driver of inflammation that signals the liver to produce these proteins—these markers can remain in the normal range even when a patient is experiencing a disease flare or a serious infection.

Key details on how Actemra affects these tests:

Rapid Suppression: CRP and ESR levels drop rapidly after starting Actemra, often within weeks, regardless of whether the underlying disease (such as RA or GCA) is completely under control.

Masking Infections: Actemra can completely suppress CRP production, meaning a normal result cannot be used to rule out serious infections or sepsis in patients taking the medication.

Disease Monitoring: Because these markers are suppressed, they are often considered unreliable for monitoring disease activity in patients taking Actemra. Doctors often rely more on clinical symptoms (pain, fatigue, stiffness) rather than blood tests to determine if a condition like Giant Cell Arteritis (GCA) or Rheumatoid Arthritis (RA) is flaring.

Sign of Compliance: Because the drug is so effective at lowering these markers, a rise in CRP/ESR while on Actemra might actually indicate that the medication is not being taken regularly (poor compliance) rather than just a flare of disease, as indicated in user discussions.
Important Safety Note: If you are on Actemra, do not rely solely on normal CRP/ESR results to determine if you are healthy, especially if you have symptoms of infection (fever, chills, severe cough). "

I think doctors keep testing ESR and CRP values to be sure that the Actemra is working as expected and the patient is really taking the Actemra.

@sjc123
Hi @sjc123: Hmmm...my Rheumatologist did not assure me that GCA would resolve. She said that I would likely be on Tyenne for the rest of my life, but did not rule out tweaking dosage schedule at some future point. I must say that I was bummed out to hear that, as initially I was either told or read that I'd be on treatment for about 2 years, depending.....and expecting a remission. That info changed to treating forever. I've been on monthly infusions for 14 months now and weekly injections for 3 months prior to that. (Dx'd PMR/GCA both July 2024.) I was told that I MUST have the injections exactly 4 weeks apart (& only if absolutely necessary, no more than 1-2 days leeway in either direction). Thus, I am already scheduled out every 4 weeks thru December 2026 at Kaiser-Permanente! I'll see what my Rheum says about a flare (symptomatic) and CRP labs (increasing?) while on Tyenne. Perhaps the same thing yours said, but will see. They never do an ESR lab with me, just CRP. They told me that ESR is unnecessary and that only CRP is needed (post diagnosis). I can ask Rheum again about that.

For us all...maybe there will be a scientific breakthrough in the future--who knows?

Hafta add one incredible silver lining for me: Tyenne (& possibly the prednisone prior?) seems to have shut down my killer 3-4-day migraines that I had 1-2x/month for 3 decades! I've only had 2 milder migraines in 17 months. Talk about the gift of time returned!!!

I sure hope that PT helps with your PMR symptoms, or whatever it is that is causing the pain.