Overall Response Rate (ORR) is a common clinical trial endpoint used in multiple myeloma trials. It tells us what percentage of patients had a noticeable reduction in their cancer after treatment within a specific time frame. In myeloma, this means the treatment worked to lower the number of cancer cells in the body.

ORR includes different levels of response, such as:

• Stringent Complete Response (sCR): This is the highest level of response, meaning there’s no detectable myeloma protein, a normal free-to-light chain ratio, and no cancer cells found in the bone marrow.
• Complete Response (CR): Standard tests show no signs of myeloma cells, indicating that the disease has completely disappeared.
• Very Good Partial Response (VGPR): There’s a big reduction in cancer cells, with at least 90% of the myeloma protein gone from the blood and urine.
• Partial Response (PR): The disease has decreased significantly in urine and blood (at least 50%) but hasn't gone completely.

Some studies might mention Stable Disease (SD), meaning the myeloma hasn’t improved or worsened. However, SD isn’t part of ORR because it doesn’t show a reduction in cancer.

ORR is important in myeloma because it quickly shows how well a treatment is working, especially in early-phase trials where long-term outcomes have yet to be measured. It helps researchers decide if a new therapy is worth investigating further, even though ORR doesn’t tell us how long responses last or how long the treatment keeps cancer from progressing.

How Are Response Rates Represented?

Let's walk through how to read this mock-up bar graph that shows how well different treatments worked.

What You're Looking At:

• Two main bars side by side: standard treatment (left) and new treatment (right)
• Each bar is divided into colored sections showing different levels of response, as explained above

How to Read the Results:

1. Overall Response Rate (ORR): When you look at the full height of each bar, you'll see that
   • For every 100 patients who received the standard treatment, 70 showed some level of response, while for every 100 patients who received the new treatment, 85 showed some level of response.
   • This tells us that the new treatment helped 15% more patients achieve at least a partial response to therapy.
2. Breaking down the responses: 
   • Each colored section shows how many patients achieved that specific level of response
   • The deeper the response (higher up the bar), the better the outcome
   • You can see how the responses are distributed from PR up to sCR
3. Deep response rates (VGPR or better): Looking at the sections marked by the line on the side of each bar
   • With the standard treatment, about 57 out of 100 patients reached a very good partial response or better, but with the new treatment, this increased to 74 out of 100 patients.
   • The larger top sections in the new treatment bar show that more patients were able to achieve better responses to therapy.

What This Means for You:

• Higher overall bars mean more patients responded to the treatment.
• The colored sections help you see not just how many patients responded but how well they responded.
• These graphs help you understand your odds of significantly reducing the number of myeloma cells with each treatment and, therefore, many of the symptoms associated with the disease.