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How long does it take for Xiaflex to work?

Medically reviewed by Carmen Pope, BPharm. Last updated on Sep 7, 2023.

Official answer


Xiaflex starts to work within 30 days for some people with Dupuytren’s Contracture, but some people may have to wait up to 90 days to see a result. Up to 39% report an improvement after 30 days which increases to up to 64% by 90 days.

When Xiaflex is used to treat Peyronie’s Disease, it may take several months for it to start working although some improvements may be noticed within the first month or two. Maximal effects may not be seen for at least 24 weeks. Trials reported on outcomes at 52 weeks.

How well does Xiaflex work for Dupuytren’s contracture?

For Dupuytren’s contracture, two trials (total number =374 adults) investigated the effectiveness of Xiaflex at reducing the contracture of the selected primary joint (metacarpophalangeal (MP) or proximal interphalangeal (PIP) joint) to within 0 to 5 degrees of normal, 30 days after the last injection of that joint. Injections were given on days 0, 30 and 60 and results were measured on days 30, 60, or 90. Up to 3 injections were given.

After the end point of the study (after 90 days), the MP or PIP joints of 64% of people in study 1 and 44% of people in study 2 had improved to within 0 to 5 degrees of normal.

39% of people had improved to within 0 to 5 degrees of normal after 1 injection (at day 30) in study 1 and 27% had improved to within 0 to 5 degrees of normal by day 30 in study 2.

How successful is Xiaflex for Dupuytren’s contracture?

Xiaflex is successful at resolving Dupuytren’s contracture to within 0 to 5 degrees of normal after up to 3 injections (by day 90) in 44% to 64% of people.

Xiaflex may work better for people who have the contracture in their metacarpophalangeal (MP) joint as the studies report that the contracture resolved to within 0 to 5 degrees of normal in 77% of people with an MP contracture compared to only 40% of people with PIP contracture. Only 7% (study 1) and 5% (study 2) of people reported an improvement with a placebo treatment (which was a saline treatment).

How well does Xiaflex work for Peyronie’s disease?

The two trials that investigated the effectiveness of Xiaflex for Peyronie’s disease reported on two outcomes after 52 weeks:

  • Percentage change in abnormal curvature and
  • Reduction in patient-reported bother regarding Peyronies disease and its effects on the man’s quality of life.

In Study 1 there was a significant change in the baseline deformity of -35.0% which compared with -17.8% for those administered placebo (an inactive treatment), making an overall difference of 17.2%. There was also a significant improvement of 2.8 points in the patient-reported bother score, which was 1.2 points higher than that observed with placebo.

In study 2, there was a significant change in the baseline deformity of -33.2% with Xiaflex compared to -21.8% with placebo making an overall difference of 11.4%. There was also a significant change in patient-reported bother score of 2.6 points, with an overall improvement of 1.1 compared with placebo.

These trials used 4 treatment cycles of Xiaflex or placebo, each given 6 weeks apart (weeks 0, 6, 12, 18) with a follow up at 24 and 52 weeks. Patients were also asked to perform penile modelling at home which consisted of gently stretching the penis 3 times a day for 6 weeks after each treatment cycle, and straightening the penis daily if an erection occurred without any sexual activity.

How successful is Xiaflex for Peyronie’s disease?

A 33% to 35% improvement in penile curvature was reported in two studies that investigated 832 men with Peyronies disease. These trials excluded men with a penile curvature deformity of less than 30 degrees and those with a ventral curvature deformity, an isolated hourglass deformity or a calcified plaque that could have interfered with the injection technique.

Serious side effects such as corporal rupture (penile fracture) were reported in 5 of 1044 (0.5%) Xiaflex treated patients and 9 out of 1044 (0.9%) patients reported a sudden loss of erection and/or a penile “popping” sound or sensation which could also indicate a corporal rupture. 3.7% of patients reported severe bruising. Anecdotally, blog sites report shrunken penises, lasting abdominal or back pain, a worsening of the curvature, and a decreased sex life after Xiaflex.

  • Xiaflex (collagenase) is an injectable non-surgical treatment for Peyronie's disease or Dupuytren’s contracture.
  • Brant, W. O., Reed-Maldonado, A., & Lue, T. F. (2015). Injection therapy for Peyronie's disease: pearls of wisdom. Translational andrology and urology, 4(4), 474–477.
  • Xiaflex. User ratings and Reviews.,I%20have%20had%208%20injections.%22
  • Xiaflex (collagenase clostridium histolyticum) Updated Aug 23, 2023.

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