diff --git a/crates/anthropic/src/anthropic.rs b/crates/anthropic/src/anthropic.rs
index bd72fe1ef3db09c97ea853f7691f50a202b7f5ae..bc2516b8b0f53e79a03fca40f6ce4dc5b564efc1 100644
--- a/crates/anthropic/src/anthropic.rs
+++ b/crates/anthropic/src/anthropic.rs
@@ -781,7 +781,10 @@ pub async fn stream_completion_with_rate_limit_info(
             .filter_map(|line| async move {
                 match line {
                     Ok(line) => {
-                        let line = line.strip_prefix("data: ")?;
+                        let line = line
+                            .strip_prefix("data: ")
+                            .or_else(|| line.strip_prefix("data:"))?;
+
                         match serde_json::from_str(line) {
                             Ok(response) => Some(Ok(response)),
                             Err(error) => Some(Err(AnthropicError::DeserializeResponse(error))),