Follow-up study finds evidence of delay of knee replacement with Ampion injections

Ampio Pharmaceuticals announced today some partial results of a follow-up (3.4-3.7 years) trial evaluating Ampion™ for pain due to osteoarthritis-of-the-knee after the last Ampion or saline injections in the STRUT study, exploring the effect of repeat Ampion™ injections on delaying Total Knee Replacement (TKR).

The STRUT study (AP-007, ClinicalTrials.gov NCT0184156) was a randomized, saline vehicle-controlled study to evaluate the safety and efficacy of Ampion™ when administered as three 4mL IA injections delivered every two weeks (at Baseline, Week 2, and Week 4). The trial was conducted in two phases at a US clinic:  1)  a 7-patient single-blind phase where all patients received Ampion;  2)  a 40-patient double-blind phase where patients were randomized 1:1 to Ampion or saline. The primary endpoint was change in WOMAC A pain between baseline and week 20.

The results indicate that the patients receiving Ampion were less likely to require a total knee replacement (TKR) than patients in the control group:

•  The severe KL4 patients most likely to require a TKR (n=16), treated with Ampion obtained a lower rate of TKR compared to patients treated with saline (40.0% or 4/10  vs.  83.3% or 5/6).

• The KL4 subset of patients that  were  responders (n=10) treated with Ampion also obtained a lower rate of TKR compared to patients treated with saline (14.3% or 1/7  vs.  100% or 3/3), a result which did reach significance (p=0.033).

KL 4 refers to the Kellgren and Lawrence scoring system. Grade 4 (KL4) is the highest  (most severe) grade that can be assigned and is referred to as “end stage” knee OA.

The FDA has acknowledged an unmet medical need in patients with pain due to severe knee OA, graded as Kellgren-Lawrence Grade 4 (KL 4), where there are currently no FDA approved treatments for this population.

Ampion is a low molecular weight fraction of human serum albumin (HSA) currently being developed for the treatment of pain due to osteoarthritis of the knee. The primary constituent ingredient of Ampion is aspartyl-alanyl diketopiperazine, or DA-DKP, an endogenous immunomodulatory molecule derived from the N-terminus of HSA. Based on published pre-clinical and clinical research, DA-DKP plays a significant role in the regulation of inflammation. DA-DKP is believed to reduce inflammation by suppressing pro-inflammatory cytokine production in T-cells. Ampion also contains other known small molecules that confer anti-inflammatory effects to complement the activity of DA-DKP.