醫藥產品的專利權利請求項因為涉及醫藥開發過程階段,有不同的態樣。依照聯合國貿易與永續發展國際中心出版,由Carlos Correa教授於2007年所發表有關「藥品專利審查指南:以公共衛生觀點著眼」之研究報告,揭露一般醫藥專利的態樣。該研究報告指出,醫藥專利一般可由單獨活性成分或結合活性成分而組成。報告歸納,常見的藥物專利態樣包括:(1)配方(formulations)專利、(2)鹽類(salt)專利、(3)前體(prodrugs)型態專利、(4)異構物(isomers)等類型之專利(5)藥品製造方法;或(6)結合方法與產品之專利。另外有些國家尚允許用途專利(method of use)。本文將摘要介紹Carlos報告(註1)中所整理的這些專利態樣,並參考Westlaw中「學名藥專利與FDA法律」資料庫中對於藥品專利權利態樣介紹,以及分析對於專利保護之影響。
藥品專利具有「組成物請求項」,是指一般涵蓋活性成分以及藥用載體(carriers)或賦形劑(excipients),例如填充劑(fillers)、粘合劑(binders)、分解劑(disinter grants)以及潤滑劑(lubricants)。以英國為例,2004年3月,英國專利局公布的醫藥發明專利審查基準,第114312段規定醫藥組成物的請求項(claims to pharmaceutical composition)、以及用於特定用途的組成物之專利(compositions adopted to a particular use)的審查基準。
若干國家雖然承認配方與組成專利,但一般要求配方與組成專利必須具備某些相關的效果,例如:血液的藥物釋放率可以被控制,這種效果一般是該製藥領域技藝之人所具有之普通技藝水準就可以達成的效果,因此除非有產生例外的效果,才具有進步性。例如,因為在產品中使用了一種能夠產生意料之外或驚人效果(unexpected or superising )的新賦形劑,就具有可專利性之可能性;比如,明顯降低了副作用或者大量改善了藥物的釋放,可符合進步性條件,例如以皮下裝置(subdermal device),可以長期釋放胰島素,就具有可專利性。
理論上而言,單獨的旋光對映異構體雖比外消旋混合物更具活性,但如果發現了具有旋光對映異構體的化合物化學結構式,則旋光對映異構物的新穎性就會喪失,因為從結構式就足以得知旋光對映異構體的存在。但實務上,美國專利實務仍承認異構物得申請專利,因為認為異構物的療效仍有差異,例如:可能其中一個有毒性,另一個有療效;或是一個有療效,另一個不具療效。Sanofi-Aventis行銷的藥品稱作Plavis ,美國專利號為4,847,265,其中請求項第三項記載: Hydro Sulfate of the dextrorotary isomer of methyl alpha-5rotary isomer,即針對右旋異構物申請專利。
Carlos Corres, Guidelines for the examination of pharmaceutical patent:developing a public health perspective, ICTSD, 2007.
参见Glaxo Group Ltd's Patent [2004]RPC 43. Report of Patent, Design and Trade Mark Cases (RPC). The RPC is published by Sweet & Maxwell on behalf of the Patent Office (UK)。
27. The crystalline form according to claim 25 characterized by one or more of the following:
a) unit cell parameters substantially equal to the following:
Cell dimensions
a=4.793(1) Å
b=19.914(4) Å
c=27.696(4) Å
α=90 degrees
β=94.52(1) degrees
γ=90 degrees
Space group P21/c
Molecules/asymmetric unit 1
wherein measurement of said crystalline form is at room temperature, and which is characterized by fractional atomic coordinates substantially as listed in Table 4;
b) a powder x-ray diffraction pattern comprising 2θ values (CuKα λ=1.5418 Å) selected from the group consisting of 6.4±0.1, 8.9±0.1, 11.0±0.1, 13.1±0.1, 13.6±0.1, 15.6±0.1, 19.1±0.1, 20.6±0.1, 22.1±0.1 and 23.0±0.1, at room temperature;
c) a solid state 13C NMR spectrum having substantially similar peak positions at 10.1, 23.8, 47.4, 50.4, 56.5, 67.4, 110.3 or 110.9, 118.0 or 119.8, 124.1, 126.1, 128.0, 129.0, 130.8, 131.1, 133.3, 144.0, 145.5, 155.8, 156.3, 158.6, 160.9 and 171.7 ppm, as determined on a 400 MHz spectrometer relative to TMS at zero;
d) a differential scanning calorimetry thermogram having a peak onset at about 140-144° C.;
e) thermal gravimetric analysis curve having less then 0.3% weight loss up to about 125° C.;
f) a moisture sorption isotherm having less then 0.3% moisture uptake in the range 25-75% RH at 25° C.; and/ or
g) a powder X-ray diffraction pattern substantially in accordance with that shown in FIG. 1.