MELBOURN, England, Nov. 14 /PRNewswire/ -- Cambridge Antibody Technology (Nasdaq: CATG; LSE: CAT) today announces the six month follow-up results from a Phase II clinical trial using CAT-152 (lerdelimumab; human anti-TGF(Beta)2 monoclonal antibody) in patients undergoing surgery for glaucoma and cataract. CAT-152 has been designed to prevent excessive post-operative scarring which is the major reason why glaucoma surgery can fail to lower intraocular pressure in the long term.
The trial results will be presented today at the American Academy of Ophthalmology in New Orleans by consultant ophthalmic surgeon Dr David Broadway.
The Phase II clinical trial studied 56 patients who were undergoing combined glaucoma and cataract surgery. Patients were randomised to receive either CAT-152 (36 patients) or matching placebo (20 patients) in a series of four subconjunctival injections which were given on the day of surgery (both immediately pre and post-operatively), the day after surgery and a week after surgery. The primary objective of the trial was to assess safety and tolerability of CAT-152 injection in this group of patients. A secondary objective was exploration of efficacy of CAT-152.
As previously reported in August (three month data), CAT-152 was found to be safe and well tolerated in this trial with no serious drug-related adverse events and no severe injection site reactions reported. There was no evidence of increased inflammation in the anterior chamber of the eye.
Intraocular pressure (IOP) was successfully lowered by surgery in both patient groups. Six months after operation the achieved IOP was lower in patients receiving CAT-152 (mean value 14.5 mmHg) compared to those receiving placebo (mean value 16.7 mmHg). The proportion of patients achieving IOP below 22 mmHg was: CAT-152 100%, placebo 80% (p = 0.013). At lower IOP thresholds a similar trend was seen (less than 18 mmHg: CAT-152 83%, placebo 65%; less than 15 mmHg: CAT-152 50%, placebo 30%). In the early post-operative period intervention with 5FU injection was used in 10 of 36 (28%) CAT-152 treated patients compared to 2 of 20 (10%) on placebo.
By six months after surgery resumption of long term topical IOP lowering medication was needed in 3 of 36 (8%) CAT-152 treated patients compared to 3 of 20 (15%) on placebo. One of these three placebo patients subsequently underwent repeat trabeculectomy to control IOP.
Commenting on the results, Dr David Glover, CAT's Medical Director said, ``Six months after operation, we can see a clearer trend towards a better long- term outcome in those patients treated with CAT-152 than was apparent in the three month follow-up results, highlighting the importance of long-term follow-up after surgery for glaucoma. We were particularly pleased that these trial results are being presented at the highly prestigious American Academy of Ophthalmology today.''
Notes to Editors:
Glaucoma and Glaucoma Surgery
* Glaucoma is the name for a group of eye conditions in which the optic
nerve is damaged at the point where it leaves the eye. The main cause
of this damage is raised pressure inside the eye (intraocular
pressure, IOP).
* Glaucoma affects 2% of people aged over 40 years, and the percentage
of people affected rises with age such that 5% of people over 65 are
affected, rising to around 8% of those over 75.
* Glaucoma is a major source of blindness. Treatment is generally aimed
at lowering the pressure in the eye to prevent long term damage to
eyesight. Eye drops are the mainstay of treatment but more than 10%
of patients require surgery to control pressure.
* Trabeculectomy is the most commonly performed surgical operation for
glaucoma. Surgery lowers IOP by improving the drainage of fluid in the
eye.
* Scarring is the main cause of failure of surgery for glaucoma. There
are no approved treatments to prevent this scarring. CAT has estimated
that up to 250,000 patients undergoing operations in the US and
Western Europe each year could benefit from treatment with CAT-152.
* Quite commonly surgeons will combine surgery for glaucoma with a
cataract extraction and intraocular lens implantation. Both glaucoma
and cataract are conditions that increase in prevalence with
increasing age hence they may co-exist in elderly patients.
* Patients are generally classified as failures of surgery if there is a
need to resume topical medication and/or further surgery is required.
Attainment of IOP levels such as 22 mmHg or 18 mmHg are widely used.
CAT-152
* CAT-152 is a fully human anti-TGF(Beta)2 monoclonal antibody developed
by CAT to specifically neutralise the cytokine TGF(Beta)2,
overactivity of which is believed to cause scarring in and around the
eye. CAT-152 is being developed as a treatment to prevent scarring in
the eye following glaucoma surgery.
* Two year follow-up results from a Phase I/IIa clinical trial in 24
patients undergoing simple glaucoma surgery released in April 2001
showed that the group of patients treated with CAT-152 at the time of
surgery achieved significantly lower intraocular pressure (IOP) than
those treated with placebo. Mean values two years after surgery were
13.6 mmHg (CAT-152) compared to 17.7 mmHg (placebo) (p= 0.004). The
pressure difference was apparent despite clear trends for less use of
post-operative injections and less use of topical medication in the
CAT-152 group. The results were presented at the Association for
Research in Vision in Ophthalmology (ARVO) 2001 conference in Fort
Lauderdale, Florida, USA.
* Three month follow-up results of a Phase II clinical trial using CAT-
152 in combined cataract and glaucoma surgery were announced 22 August
2001.
Efficacy
* Efficacy is measured in terms of reduced need for intervention post
surgery, or in terms of lower IOP. |
