Swedish Biotech Dex­Tech Med­ical shoots for bil­lion dol­lar prostate can­cer mar­ket — con­cludes phI­Ib study ear­ly

When Dan­ish biotech pow­er­house Bavar­i­an Nordic an­nounced its can­cer vac­cine Prost­vac was a phI­II bust in Sep­tem­ber 2017, a gap opened in the Scan­di­na­vian com­pet­i­tive land­scape of cas­tra­tion-re­sis­tant prostate can­cer ther­a­pies. Less than a year lat­er, Swedish mi­cro-cap biotech Dex­Tech Med­ical seems ready to fill that void as it wraps up a clin­i­cal study ear­ly, with promis­ing da­ta for its drug can­di­date Os­teoDex.

An in­cur­able dis­ease with high busi­ness val­ue
Every year rough­ly 750 000 Amer­i­can men are di­ag­nosed with prostate can­cer. Around 140,000 die af­ter de­vel­op­ing the most se­vere form, metasta­t­ic cas­tra­tion-re­sis­tant prostate can­cer or mCR­PC. There is no cu­ra­tive ther­a­py and the un­met med­ical need is huge, since pa­tients usu­al­ly de­vel­op drug re­sis­tance to the hand­ful of ther­a­pies cur­rent­ly avail­able on the mar­ket.

In­evitably, the dire sit­u­a­tion al­so rep­re­sents a grow­ing fi­nan­cial in­cen­tive for phar­ma com­pa­nies. Es­pe­cial­ly giv­en the fact that any promis­ing new drug can­di­date with­in this field could be a po­ten­tial block­buster, should it reach the mar­ket. Ac­cord­ing to Data­mon­i­tor Health­care, the to­tal prostate can­cer drug rev­enues in the US, Japan and five ma­jor EU mar­kets (France, Ger­many, Italy, Spain, and the UK) will in­crease from $6.4bn in 2015 to $13.5bn in 2024 at a com­pound an­nu­al growth rate of 8.6%

Dex­tech Med­ical brings ex­per­tise in prostate can­cer
The mul­ti-bil­lion dol­lar mar­ket for mCR­PC is the pri­ma­ry tar­get for Dex­Tech Med­ical, a Swedish biotech com­pa­ny spe­cial­ized in uro­log­i­cal on­col­o­gy. The Up­p­sala-based, Spot­Light stock­mar­ket list­ed mi­cro-cap play­er has de­vel­oped its lead drug can­di­date based on the pro­pri­etary plat­form tech­nol­o­gy GuaDex us­ing dex­tran, a car­bo­hy­drate mol­e­cule, which is mod­i­fied and used as the back­bone when de­vel­op­ing new can­di­date com­pounds.

For more in­for­ma­tion on the phase IIb-study, see Clin­i­cal tri­als.

Pre­clin­i­cal re­sults in­di­cate broad tu­mor po­ten­tial
Os­teoDex, which is Dex­Tech Med­ical’s lead­ing drug can­di­date in a pipeline of four sub­stances, gives very few and mi­nor side ef­fects com­pared to oth­er cy­to­sta­t­ics. This is very im­por­tant as the cur­rent pa­tient group is sen­si­tive to treat­ment side ef­fects.

Dex­Tech’s pre­clin­i­cal stud­ies have al­so clear­ly shown that Os­teoDex has a po­ten­tial tar­get­ing ad­vanced breast can­cer with skele­tal metas­tases. In ad­di­tion, the com­pa­ny has seen sig­nif­i­cant ac­tiv­i­ty in soft tis­sue tu­mors, though skele­tal tu­mors are the pri­ma­ry tar­get.

Eu­ro­pean ref­er­ence deals
Scan­di­na­vian an­a­lyst house Bio­S­tock has, in its cov­er­age of Dex­Tech, point­ed out the many par­al­lels to Xofi­go, an­oth­er drug tar­get­ing prostate can­cer with sim­i­lar qual­i­ties to Os­teoDex, which was picked up by Ger­man phar­ma gi­ant Bay­er in 2013 when it ac­quired Nor­we­gian Al­ge­ta in a $2.9B cash deal.

A more re­cent ref­er­ence deal took place in Oc­to­ber, when US-based En­do­cyte an­nounced a bil­lion dol­lar agree­ment with Ger­man ABX GmbH for a treat­ment tar­get­ing cas­tra­tion-re­sis­tant prostate can­cer. ABX re­ceived $12 mil­lion up­front and up to 6 mil­lion En­do­cyte shares if all terms in the deal are ful­filled. In ad­di­tion, ABX will re­cieve mile­stone pay­ments amount­ing to up to $160 mil­lion and two-dig­it roy­al­ties on fu­ture sales.

Ra­dioac­tive iso­topes such as En­do­cyte’s and Bay­er’s treat­ments men­tioned above are not un­com­pli­cat­ed as a treat­ment op­tion since they in­volve both ra­dio-safe­ty reg­u­la­tions and spe­cial de­part­ments with­in hos­pi­tals. Con­sid­er­ing that they al­so can cause se­ri­ous side-ef­fects on both kid­neys and bone mar­row, there is cer­tain­ly a need for drugs that show high ef­fi­ca­cy with less side ef­fects. An­oth­er ben­e­fit of non-ra­dioac­tive drugs would be the sim­pler lo­gis­tics, i.e. the prac­ti­cal han­dling of the sub­stance at treat­ment clin­ics.

The founders of Dex­Tech Med­ical. Prof. Sten Nils­son (left) and CEO An­ders R Holm­berg (right)

A bench­mark be­tween Os­teoDex and Xofi­go shows sim­i­lar­i­ties
Bay­er’s drug Xofi­gohas the same tar­get as Os­teoDex (CR­PC). Both sub­stances are al­so so-called mimet­ics, mean­ing that they mim­ic the bind­ing of the nat­ur­al sub­stances to the bone. The dif­fer­ences be­tween the sub­stances in this re­gard are mi­nor; Ra-223 binds to bone as cal­ci­um, while Os­teoDex binds to the skele­ton like Py­rophos­phate, a nat­ur­al sub­stance that reg­u­lates bone min­er­al­iza­tion. Both drugs act by break­ing or in­hibit­ing the so-called “vi­cious cy­cle”, i.e. the process where bone cells and tu­mor cells are mu­tu­al­ly stim­u­lat­ing each oth­er by se­cret­ing growth fac­tors.

Sim­i­lar clin­i­cal ef­fect
The clin­i­cal ef­fect of the two sub­stances are al­so sim­i­lar in that they have lit­tle or no ef­fect on PSA (prostate-spe­cif­ic anti­gen). On the oth­er hand, both have a pro­nounced ef­fect on bone mark­ers, sub­stances that sig­nal ei­ther bone break­down or ab­nor­mal bone for­ma­tion (lyt­ic or blas­tic ac­tiv­i­ty), such as al­ka­line phos­phatase or ALP.

Prostate can­cer have a pref­er­ence to metas­ta­size to the skele­ton. Bone tis­sue con­tains two prin­ci­pal cells,  os­teoblasts that builds bone and os­teo­clasts that break it down. The sig­nal­ing be­tween bone cells and tu­mor cells stim­u­late pro­gres­sive break­down of nor­mal bone and pro­gres­sion of the metasta­t­ic growth. This is de­scribed as “the vi­cious cy­cle”, a con­di­tion which is in­cur­able and may at the very best be slowed down.

Os­teoDex’s true strength could be in a com­bined ther­a­py
Con­sid­er­ing that cas­tra­tion-re­sis­tant prostate can­cer with skele­tal metas­tases is an in­cur­able state, where all cur­rent ther­a­pies af­ter some time be­come in­ef­fec­tive, the strat­e­gy for fu­ture treat­ments is quite pos­si­bly about find­ing com­bi­na­tion reg­i­mens to max­i­mize the ben­e­fit for the pa­tient. Could a com­bo of Os­teoDex and an­oth­er drug on the mar­ket be the so­lu­tion? – It just might be.

In the­o­ry it is fea­si­ble that Os­teoDex could be the per­fect match as a sup­ple­ment to Xofi­go. Part­ly be­cause of the sig­nif­i­cant sim­i­lar­i­ties be­tween the two, and part­ly be­cause the pri­ma­ry strength of the two drugs is that they are mimet­ic. While Xofi­go is ab­sorbed in the skele­ton just like cal­ci­um, Os­teoDex binds as py­rophos­phate and is per­ceived by the tu­mor cell as a polyamine that the tu­mor cell needs to grow.

Dex­Tech Med­ical hopes to re­peat the Bay­er/Al­ge­ta deal
While there are sev­er­al re­cent ref­er­ence deals with­in prostate can­cer, such as the En­do­cyte/ABX-deal men­tioned ear­li­er or As­traZeneca‘s $2.8 bil­lion trans­ac­tion in which the com­mer­cial rights of Zo­ladexfor the treat­ment of prostate can­cer were trans­ferred to TerSera Ther­a­peu­tics, there is one deal with an in­di­rect link to Dex­Tech Med­ical. When Bay­er in 2013 ac­quired the Nor­we­gian prostate can­cer com­pa­ny Al­ge­ta for $2.9 bil­lion, one of those re­spon­si­ble for de­sign­ing the clin­i­cal tri­als in the de­vel­op­ment of their drug Xofi­go, was Sten Nils­son, Pro­fes­sor of On­col­o­gy and co-founder of Dex­Tech Med­ical.

And the big play­ers in this field are con­tin­u­ous­ly scout­ing for a more ef­fec­tive treat­ment with min­i­mal side ef­fects. A few of these, be­sides the above-men­tioned com­pa­nies, are Bris­tol-My­ers Squibb, Abzena, Telix, Thresh­old Phar­ma and OBI Phar­ma, in which re­cent merg­er ac­tiv­i­ties and li­cens­ing agree­ments re­lat­ing to Dex­Tech Med­ical’s in­ter­est area have been seen.

Col­lab­o­ra­tion with EY to find the per­fect in­dus­try part­ner
As Dex­Tech Med­ical’s phase IIb study with Os­teoDex is near­ing con­clu­sion with da­ta read­out planned in the sec­ond half of 2018, the com­pa­ny has ini­ti­at­ed a fo­cused ef­fort to­geth­er with glob­al con­sult­ing firm EY‘s biotech ex­perts to iden­ti­fy ap­pro­pri­ate in­dus­try part­ners. This could prove an im­por­tant prepara­to­ry mea­sure, as the Swedish biotech play­er heads to­wards the un­veil­ing of fi­nal clin­i­cal re­sults and ef­fi­ca­cy da­ta which it hopes will con­firm the promis­ing re­sults from pre­vi­ous stud­ies.

Read more about Dex­Tech Med­ical here: http://dex­techmed­ical.com/en/